(2,5-dioxoimidazolidin-i-yl)-n-hydroxy-acetamides as metalloproteinase inhibitors

ABSTRACT

The invention provides compounds of the formula (I) 
     
       
         
         
             
             
         
       
         
         
           
             wherein the variables are as defined in the specification. 
             The compounds of the invention are inhibitors of metalloproteinase MMP-12 and are among other things useful for the treatment of obstructive airway diseases, such as chronic obstructive pulmonary disease (COPD).

TECHNICAL FIELD

This invention relates to novel compounds which are selective inhibitorsof matrix metalloproteinases, especially metalloproteinase 12 (MMP-12),processes for their preparation, pharmaceutical compositions containingthem and their use in therapy.

BACKGROUND TO THE INVENTION

Metalloproteinases represent a super family of proteinases (enzymes),whose numbers have increased dramatically in recent years. Based onstructural and functional considerations, these enzymes have beenclassified into families and subfamilies N. M. Hooper, FEBS letters 354,1-6 (1994). Examples of metalloproteinases include the matrixmetalloproteinases (MMPs), which is a family of zinc containingendopeptidases, such as the collagens (MMP-1, MMP-8, MMP-13, MMP-18),the gelatinases (MMP-2, MMP-9), the stromelysins (MMP-3, MMP-10,MMP-11), matrilysin (MMP-7, MMP-26), metalloelastase (MMP-12) enamelysin(MMP-20), the MT-MMPs (MMP-14, MMP-15, MMP-16, MMP-17, MMP-24, MMP-25).

The MMPs is a family of zinc containing endopeptidases which are capableof cleaving large biomolecules like the collagens, proteoglycans andfibronectins, a process necessary for the growth and remodelling oftissues such as embryonic development and bone formation under normalphysiological conditions. Expression is upregulated by pro-inflammatorycytokines and/or growth factors. The MMP's are secreted as inactivezymogens which, upon activation, are subject to control by endogenousinhibitors, for example, tissue inhibitor of metalloproteinases (TIMP)and α-macroglobulin. Chapman, K. T. et al., J. Med. Chem. 36, 4293-4301(1993); Beckett, R. P. et al., DDT 1, 16-26 (1996). The characterizingfeature of diseases involving the enzymes appears to be a stoichiometricimbalance between active enzymes and endogenous inhibitors, leading toexcessive tissue disruption, and often degradation. McCachren, S. S.,Arthritis Rheum. 34, 1085-1093 (1991).

Over-expression and activation of MMPs have been linked with a widerange of diseases such as cancer, tumour metastasis, rheumatoidarthritis, osteoarthritis, chronic inflammatory disorders such asemphysema, cardiovascular disorders such as atherosclerosis, cornealulceration, dental diseases such as gingivitis and periodontal disease,and neurological disorders such as multiple sclerosis. Chirivi, R. G. S.et al., Int. J. Cancer, 58, 460-464 (1994); Zucker, S., Cancer Research,53, 140-144 (1993). In addition, a recent study indicates that MMP-12 isrequired for the development of smoking-induced emphysema in mice.Science, 277, 2002 (1997). MMP-12, also known as macrophage elastase ormetalloelastase, was initially cloned in the mouse by Shapiro et al., J.Biological Chemistry, 267, 4664 (1992) and in man by the same group in1995. Structurally, the proMMP-12 consists of a pro-domain, a catalyticdomain containing the zinc binding site and a C-terminal hemopexin-likedomain. Recombinant human MMP-12 can be activated by autocatalysis asdescribed below and reviewed by Shapiro et al “Macrophage Elastase” inHandbook of Proteolytic Enzymes 2004 (Eds A J Barrett et al) pp 540-544Academic Press, San Diego.

MMP-12 is preferentially expressed in activated macrophages and itsexpression in monocytes can be induced by cytokines such as GM-CSF andCD-40 signalling. In addition to elastin, MMP-12 can degrade a broadspectrum of substrates, including type IV collagen, fibronectin,laminin, vitronectin, proteoglycans, chondroitin sulphate, myelin basicprotein, alpha-one chymotrypsin and plasminogen. It can also activateMMP-2 and MMP-3. MMP-12 is required for macrophage mediated proteolysisand matrix invasion in mice. MMP-12 is proposed to have a direct role inthe pathogenesis of aortic aneurisms and in the development of pulmonaryemphysema that results from chronic inhalation of cigarette smoke, woodsmoke and urban smogs.

MMP-12 has been shown to be secreted from alveolar macrophages fromsmokers Shapiro et al., J. Biological Chemistry, 268, 23824, (1993) aswell as in foam cells in atherosclerotic lesions Matsumoto et al., Am.J. Pathol, 153, 109, (1998). A mouse model of COPD is based on challengeof mice with cigarette smoke for six months, two cigarettes a day sixdays a week. Wildtype mice developed pulmonary emphysema after thistreatment. When MMP-12 knock-out mice were tested in this model theydeveloped no significant emphysema, strongly indicating that MMP-12 is akey enzyme in the COPD pathogenesis. The role of MMPs such as MMP-12 inCOPD (emphysema and bronchitis) is discussed in Anderson and Shinagawa,Current Opinion in Anti-inflammatory and ImmunomodulatoryInvestigational Drugs: 29-38 (1999). It was recently discovered thatsmoking increases macrophage infiltration and macrophage-derived MMP-12expression in human carotid artery plaques Kangavari (Matetzky S,Fishbein M C et al., Circulation 102, (18), 36-39 Suppl. S, Oct. 31,(2000).

Apart from the role of these potentially very destructive enzymes inpathology, the MMPs play an essential role in cell regrowth and turnoverin healthy tissue. Broad spectrum inhibition of the MMPs in the clinicalsetting results in musculoskeletal stiffness and pain. H. S. Rasmussenand P. P. McCann, Pharmacol. Ther., 75, 69-75 (1997). This side effectand others associated with broad spectrum inhibition may be enhanced inchronic administration. Thus, it would be advantageous to provideselective MMP inhibitors.

The inhibition of such MMP-12 activities is considered to contribute tothe improvement and prevention of the above discussed diseases caused byor related to the activity of MMP-12. Therefore, the development ofMMP-12 inhibitors has been desired.

A number of metalloproteinase inhibitors are known and described in theliterature, (see for example the reviews of MMP inhibitors by Beckett R.P. and Whittaker M., 1998, Exp. Opin. Ther. Patents, 8 (3):259-282.Whittaker M. et al, 1999, Chemical Reviews 99 (9): 2735-2776) review awide range of known MMP inhibitor compounds. They state that aneffective MMP inhibitor requires a zinc binding group, i.e. a functionalgroup capable of chelating the active site zinc(II) ion, at least onefunctional group which provides a hydrogen bond interaction with theenzyme backbone, and one or more side chain which undergo effective vander Waals interactions with the enzyme subsites. Zinc binding groups inknown MMP inhibitors include carboxylic acid groups, hydroxamic acidgroups, sulfhydryl groups or mercapto groups.

Despite the potent affinity of hydroxamic acid as zinc coordinator,hydroxamic acid inhibitors demonstrate a considerable degree ofspecificity within the MMP family: a potent inhibitor of one member ofthe MMP family, may have only minimal potency against another MMP familymember. This exhibited specificity typically relies on the identity ofthe other parts of the inhibitors, e.g. the P1, P2, P3 and P4 units.Without in any way wishing to be bound by theory, or the ascription oftentative binding modes for specific variables, the notional conceptsP1, P2, P3 and P4 are used herein for convenience only and havesubstantially their conventional meanings, as illustrated by Schechter &Berger, (1976) Biochem Biophys Res Comm 27 157-162, and denote thoseportions of the inhibitor believed to fill the S1, S2, S3 and S4subsites respectively of the enzyme, where S1 is adjacent the cleavagesite and S4 remote from the cleavage site.

There are several patents which disclose hydroxamate-based inhibitors ofmetalloproteases or analogous enzymes.

WO02/028829 describes inhibitors of peptide deformylase (PDF) useful forexample in the development of new antibacterial drugs. PDF is abacterial enzyme which shares several structural features in common withzinc metalloproteases. PDF does not cleave a peptide bond, but rathercleaves off the N-formyl group from the terminal N-formyl methioninewhich characterises the nascent bacterial polypeptide chain. Despite thefact that the compounds of WO02/028829 comprise a hydroxamic acid groupthe SAR (structure activity relationship) exhibited by these inhibitorsis not helpful to the design of specific inhibitors of the endopeptidaseMMP-12. An endopeptidase cleaves within a peptide chain, and thereforethe protease typically recognises a number of amino acid residues aroundthe intended cleavage site. In contrast PDF is intended to cleave aterminal group on the first amino acid of bacterial proteins of verydifferent sequence. Accordingly the selectivity of PDF is predicated onrecognition of the N-formyl.methionine terminal residue rather than theidentity of the adjacent amino acids.

US 3003/0134827 discloses compounds having a hydroxyacetamide moietylinked to a broad range of cyclic amides as inhibitors of MMPs inparticular MMP-3, aggrecanase and TNF-α-converting enzyme (TACE).Although hydantoin is postulated as one of many such cyclic amides, US2003/0134827 discloses no concrete examples of compounds within thescope of this invention. As demonstrated in the following biologicalexamples, the compounds of the invention achieve potent MMP-12inhibition while at the same time being highly selective against theenzymes addressed in US 2003/0134827.

U.S. Pat. No. 6,462,063 discloses substituted hydantoin hydroxamatescapable of inhibiting C-proteinase. In contrast to the compounds of theinvention defined below, the compounds of U.S. Pat. No. 6,462,063 have ahydroxamic acid linked to a carbon atom of the hydantoin ring via achain comprising, apart from the acid function, at least three atoms. Byvarying the length of the hydroxamic acid carrying chain and thesubstitution pattern of the hydantoin ring, the binding properties tothe enzyme and hence the specificity of the inhibitor will be altered.The hydroxamate function of U.S. Pat. No. 6,462,063 is thus sitting onthe other side of the hydantoin ring compared to the compounds of theinvention defined below and is also disposed further out from thehydantoin These kind of structural variations between the class ofcompounds disclosed in U.S. Pat. No. 6,462,063 and inhibitors based onhydantoin hydroxamates wherein the hydroxamic acid is linked to anitrogen atom of a hydantoin group via a one atom chain, will render theSAR exhibited by the compounds of U.S. Pat. No. 6,462,063 of norelevance to the design of specific inhibitors of MMP-12

WO02/074750 discloses a new class of compounds that act as MMPinhibitors wherein the zinc binding group of the inhibitor isconstituted of a five membered ring structure such as a hydantoin group.The zinc binding ring structure is attached to one or more functionalgroups or side chains which are disposed at an appropriate angle anddistance to recognise the characteristic sequence around the appropriateMMP12 cleavage site. The mode of binding to the enzyme of this class ofzinc-binding inhibitors will thus differ substantially from that ofcompounds having other zinc binding groups, such as hydroxamic acidadjacent a hydantoin core, in that coordination of the hydroxamate zincbinding group will displace the hydantoin away from the structural zinc.Any further substituents opposed from the hydroxamate will also bedisplaced away from the structural zinc and will interact with otherparts of the enzyme. Due to this different binding mode of the compoundsdisclosed in WO02/074750 compared to hydantoin hydroxamates, the SARfound for the P1, P2, P3 and P4 units of the compounds of WO02/074750 isnot relevant to the design of new MMP inhibitors based on a hydantoinhydroxamate scaffold.

Similarly, US 2005/0171096 discloses hydantoin derivatives alleged to beinhibitors of matrix metalloproteinases and TACE although no guidance asto the specificity of the inhibitors is given. The compounds of US2005/0171096 do not bear a hydroxamic acid or conventional zinc-bindinggroup. This suggests that that the hydantoin is the zinc binding groupand hence the SAR exhibited by the P1, P2 and P3 units of thesecompounds is different from that of an inhibitor based on a hydantoinsubstituted with a hydroxamic acid carrying side chain.

As foreshadowed above, we have now discovered a particular configurationof hydroxamic hydantoins that are inhibitors of metalloproteinases andare of particular interest in selectively inhibiting MMPs such as MMP-12and have desirable activity profiles. The compounds of this inventionhave beneficial potency, selectivity and/or pharmacokinetic properties.

DISCLOSURE OF THE INVENTION

In accordance with the present invention, there is provided a compoundof formula (I) or a pharmaceutically acceptable salt or solvate thereof:

wherein;

-   -   R¹ is C₁-C₆alkyl, C₀-C₃alkandiylcarbocyclyl,        C₀-C₃alkandiylheterocyclyl,    -   R² is carbocyclyl or heterocyclyl;    -   R³ is H or C₁-C₄alkyl;    -   R⁴ is H or C₁-C₄alkyl;    -   each R⁵ and R^(5′) is independently H, C₁-C₄alkyl or halo; or    -   R⁴ and an adjacent R^(5′) together define a double bond;    -   each R⁶ and R^(6′) is independently H, C₁-C₄alkyl or halo; or    -   R⁵ and an adjacent R⁶ together define a double bond; or    -   R⁵, R^(5′) and an adjacent R⁶ and R^(6′) together define a        triple bond;    -   n is 1-3, m is 0-3;    -   D is absent, or D is an ether, thioether, amine, amide,        carbamate, urea or sulphonamide linkage; whereby the group        (CR⁵R^(5′))_(n)-D-(CR⁶R^(6′))_(m) has at least 2 chain atoms;    -   X and Y are independently O or S;        and wherein    -   each C₁-C₄alkyl is optionally substituted with 1 to 3 halo or an        hydroxyl;    -   each C₁-C₆alkyl, carbocyclyl or heterocyclyl (including those in        any C₀-C₃alkanediylcarbocyclyl or C₀-C₃alkanediylheterocyclyl        group) is independently optionally substituted with 1 to 3        substituents selected from halo, oxo, cyano, azido, nitro,        C₁-C₆alkyl, C₀-C₃Alkdiylcarbocyclyl, C₀-C₃Alkdiylheterocyclyl,        Z—NRaRb, Z—O-Rb, Z—S—Rb, Z—C(═NOH)Rb, Z—C(═O)Rb, Z—(C═O)NRaRb,        Z—NRaC(═O)Rb, Z—NRaSO_(p)Rb, Z—S(═O)_(p)Rb, Z—S(═O)_(p)NRaRb,        Z—C(═O)ORb, Z—OC(═O)Rb, Z—NRaC(═O)ORb or Z—OC(═O)NRaRb; wherein;    -   each C₀-C₃Alkdiyl is independently a bond, a C₁-C₃ straight or        branched, saturated carbon chain or a C₂-C₃ straight or branched        unsaturated carbon chain; the carbocyclyl or heterocyclyl moiety        of any C₀-C₃Alkdiylcarbocyclyl, C₀-C₃Alkdiylheterocyclyl is        optionally substituted 1 to 3 times with substituents selected        from halo, oxo, cyano, azido, nitro, C₁-C₄alkyl, Z—NRaRc,        Z—O-Rc, Z—S—Rc, Z—C(═O)Rc, Z—(C═O)NRaRc, Z—NRaC(═O)Rc,        Z—NRaSO_(p)Rc, Z—S(═O)_(p)Rc, Z—S(═O)_(p)NRaRc, Z—C(═O)ORc,        Z—OC(═O)Rc, Z—NRaC(═O)ORc or Z—OC(═O)NRaRc;        -   each Z is independently a bond or C₁-C₃alkanediyl;    -   each Ra is independently H or C₁-C₄alkyl;

each Rb is independently H or C₁-C₆alkyl, C₀-C₃Alkdiylcarbocyclyl,C₀-C₃Alkdiylheterocyclyl;

-   -   or Ra and Rb together with an adjacent N atom define        pyrrolidine, piperidine, morpholine, piperazine or N-methyl        piperazine;    -   Rc is H or C₁-C₄alkyl;    -   or Rc and Ra together with an adjacent N atom define        pyrrolidine, piperidine, morpholine, piperazine or N-methyl        piperazine    -   each p is independently 1 or 2;        and pharmaceutically acceptable salts and solvates thereof.

In one embodiment of the invention the R¹ group comprises an optionallysubstituted alkyl chain, especially branched C₂-C₆alkyl chains.Preferably the branch occurs at position 1, adjacent the backbone of theinhibitor, as shown in the partial structure:

where R1′ is CH₃, CH₂CH₃, C₁haloalkyl, halo, hydroxy;

-   -   R1″ is H, CH₃, CH₂CH₃, C₁haloalkyl, halo, hydroxyl;    -   R¹* is C₁-C₅ optionally substituted alkyl, for example        substituted with 1-3 substituents independently selected from        carbocyclyl, heterocyclyl, ZNRaRb, nitro, hydroxyl, cyano,        carboxy, oxo, halo, C₁-haloalkyl, C₁-C₄alkyl, C₁-C₄alkoxy, C_(r)        C₄alkanoyl or carbamoyl groups.

Representative values of R¹ thus include 1-methylpropyl,1,1-dimethylpropyl, 1-ethyl-1-methyl propyl, 1,1 di methyl butyl,1,1-diethyl propyl, 1-ethyl propyl, 1-methyl butyl, 1,2-dimethylpropyl.Currently preferred values of R¹ include i-propyl, sec.butyl andtert.butyl.

A moiety such as an optionally substituted carbocyclyl or an optionallysubstituted heterocyclyl distanced 1-5 atoms from the backbone of theinhibitor at the position of R¹ can be used to alter the lipophilicityof the compounds of the invention. It is believed that an appropriatechoice of this moiety will confer any lipophilic/hydrophiliccharacteristics to the inhibitors required to improve certainproperties, i.a. their DMPK properties.

Accordingly, suitable values for R¹* are C₁-C₅alkyl substituted withcarbocyclyl or C₁-C₅alkyl substituted with heterocyclyl wherein saidcarbocyclyl and heterocyclyl are optionally substituted 1-4 times withsubstituents selected from C₁-C₃alkyl, oxo and halo. Preferredstructures for R¹ thus include:

wherein n is 0, 2, 3 or 4.

In other embodiments of the invention, the C₀-C₃alkandiylcarbocyclyl asR¹ has methylene as the C₀-C₃alkandiyl component and a C₅ or C₆monocyclic ring as the carbocyclyl component. Representative values ofR¹ in this embodiment thus include (optionally substituted): benzyl,cyclohexylmethyl-, 1-methylcyclohexylmethyl-, cyclopentylmethyl-,1-methylcyclopentylmethyl, where the optional substituents are asoutlined above.

In a preferred embodiment of the invention, theC₀-C₃alkandiylcarbocyclyl as R¹ has a bond as the C₀-C₃alkandiylcomponent and a C₅ or C₆ monocyclic ring as the carbocyclyl component.Representative values of R¹ in this embodiment thus include (optionallysubstituted): phenyl, or preferably cyclohexyl or cyclopentyl, where theoptional substituents are as outlined above.

In other embodiments of the invention, the C₀-C₃alkandiylheterocyclyl asR¹ has methylene as the C₀-C₃alkandiyl component and a 5 or 6 memberedaromatic, partially saturated, or unsaturated monocyclic ring as theheterocyclyl component. Representative values of R¹ in this embodimentthus include (optionally substituted): pyrrolylmethyl-,pyrrolinylmethyl-, pyrrolidinylmethyl-, thiazolylmethyl, pyridylmethyl-,pyrimidinylmethyl-, piperidylmethyl-, piperazinylmethyl- ormorpholinylmethyl, where the optional substituents are as outlinedabove.

In other embodiments of the invention, the C₀-C₃alkandiylheterocyclyl asR¹ has a bond as the C₀-C₃alkandiyl component and a 5 or 6 memberedaromatic, partially saturated, or unsaturated monocyclic ring as theheterocyclyl component. Representative values of R¹ in this embodimentthus include (optionally substituted): pyrrolyl, pyrrolinyl,pyrrolidinyl, thiazolyl, pyridyl, pyrimidinyl, piperidyl-, piperazinylor morpholinyl; where the optional substituents are as outlined above.

In typical embodiments of the invention the chiral center to which theR¹ group is attached has the R stereochemistry as shown in the partialstructure:

This stereochemistry corresponds to a D-amino acid, which is unexpectedin the context of an inhibitor of an enzyme such as a protease. Suchenzymes cleave proteins which are universally composed of L-amino acids.The recognition sites of most proteases thus prefer L-configurations.The compounds of the invention may be administered as the racemate atR¹, but are preferably administered as pure or substantiallyenantiomerically pure preparations, such as at least 90% ee at R¹,preferably at least 95%, such as >97% ee.

In some embodiments of the invention both of X and Y are ═S or one of Xand Y is ═S and the other is ═O, especially wherein X is ═O. It iscurrently preferred that both X and Y are ═O.

In typical embodiments of the invention, the steric center of theimidazoline ring to which the —(CR⁵R^(5′))_(n)-D-(CR⁶R^(6′))_(m)—R²group is attached has the S stereochemistry, as depicted in the partialstructure:

The compounds of the invention may be administered as the racemate atthis position, but are preferably administered as pure or substantiallyenantiomerically pure preparations, such as at least 90% ee at thisposition, preferably at least 95%, such as >97% ee.

In other embodiments of the invention, R⁴ and an adjacent R⁵ togetherdefine an olefinic bond forming part of the linkage to R²:

In this embodiment, D will typically be absent, m will be 1 or 2 andeach R⁶/R^(6′) is H.

It is currently preferred that the stereochemistry at the chiral centerto which R¹ is attached and at the chiral center to which the—(CR⁵R^(5′))_(n)-D-(CR⁶R^(6′))_(m)—R² group is attached have the R and Sstereochemistries respectively.

Representative values of D include S, NH, NMe, NH(C═O)C(═O)NH, NH(═O)NH,NH(C═O)O and OC(═O)NH.

Currently preferred values for D include O, i.e. an ether linkage or Dis absent (i.e. the (CR⁵R^(5′))_(n)-D-(CR⁶R^(6′)), function is aC₁-C₆alkandiyl chain.

Conveniently the —(CR⁵R^(5′))_(n)-D-(CR⁶R^(6′))_(m)— group has in total2 or 3 chain atoms, especially:

-   -   —CH₂CH₂— (2), —CH₂CH₂CH₂— (3),    -   —CH₂O— (2), —CH₂OCH₂— (3), —CH₂CH₂O— (3),    -   —CH₂—NH— (2), —CH₂CH₂NH— (2),    -   —CH₂OC(═O)NH— (4), —CH₂NH(C═O)O— (4).

The numbers in brackets after each —(CR⁵R^(5′))_(n)-D-(CR⁶R^(6′)), groupindicate the number of chain atoms.

It is currently preferred that n and m are each 1 and D is absent, i.e.the —(CR⁵R^(5′))_(n)-D-(CR⁶R^(6′))_(m)— group is —CH₂CH₂—.

In some embodiments of the invention each R⁵, R^(5′) and each R⁶, R^(6′)(if present) are H, but the invention extends to branched or substitutedstructures, such as those wherein R⁵ and/or R^(5′) on any one carbonatom is, for example methyl, i-propyl, t-butyl or fluoro. To avoidasymmetric centers it can be advantageous that both R⁵ and R^(5′) and/orR⁶ and R^(6′) on any one carbon atom are the same, typically, H, F orMe.

In some embodiments of the invention, D is absent and adjacent R⁵ and R⁶together define a cis or trans double bond:

In this embodiment n and m are typically 1 and the adjacent R^(5′) andR^(6′) are H. In the event that n or m is >1 the R⁵, R^(5′) R⁶ andR^(6′) of any such further chain atoms are generally H.

In other embodiments of the invention, D is absent and adjacent R⁵,R^(5′) R⁶ and R^(6′) together define a triple bond:

In one embodiment of the invention R² as carbocyclyl is an optionallysubstituted aromatic ring structure, such as naphthyl or indanyl andespecially phenyl.

In another embodiment of the invention R² as heterocyclyl is anoptionally substituted, aromatic ring structure, such as a monocyclicring selected from pyrrole, furan, thiophene, pyrazole, pyrazoline,imidazole, oxazole, isooxazole, thiazole, isothiazole, triazole,oxadiazole, furazan, thiadiazole, tetrazole, pyridine, pyridazine,pyrimidine, pyrazine, thiazine, triazine; or a bicyclic ring selectedfrom thienobifuran, indole, isoindole, benzofuran, isobenzofuran,indoline, isoindoline, benzothiophene, isobenzothiophene, indazole,benzimidazole, benzthiazole, purine, quinoline, isoquinoline, chromane,isochromane, cinnolene, quinazoline, quinoxaline, napthyridine,phthalazine or pteridine.

It is currently preferred that R² is an optionally substituted, aromaticmonocyclic ring, especially optionally substituted: pyrrolyl, thiazolyl,pyridyl or pyrimidinyl, and particularly optionally substituted phenyl.

In some embodiments an optional substituent to R² is located at thepara, ortho or meta position relative to the—(CR⁵R^(5′))_(n)-D-(CR⁶R⁶)_(m)— linkage. Typical such substituentsinclude C₁-C₄alkyl, such as methyl, haloC₁-C₂alkyl, such as fluoromethyland trifluoromethyl, —OC₁-C₄alkyl, such as methoxy, —C(═O)C₁-C₄alkyl,such as acetyl, or halo, such as fluoro. A preferred structure for R² isphenyl substituted with fluoro in the ortho position which phenyl isoptionally further substituted in the meta or preferably para position.

In some embodiments an optional substituent to R² is in the paraposition relative to the —(CR⁵R^(5′) _(n),-D-(CR⁶R^(6′))_(m)-linkage andcomprises an aromatic, monocyclic ring such as those defined above forR², especially optionally substituted: phenyl, pyrrolyl, thiazolyl,pyridyl or pyrimidinyl. This optional substituent is typically bondeddirectly to the R² ring or via a methylene, ethylene or ether linkage;as shown below

In the structure II, the R² ring has been depicted for the purposes ofillustration only as phenyl, but other ring systems will be equallyapplicable. It will be seen that the ring R² has one, but may also havetwo additional substituents R^(2′) which is the ortho or metasubstituent described in the immediately preceding paragraph.

Where R² is a 5-membered ring, the ring substituent of this aspect ofthe invention will, of course not be at the para position, but rather ata corresponding position disposed distally from the—(CR⁵R^(5′))_(n)-D-(CR⁶R^(6′)H₂)_(m)— linkage.

In structure II, the ring substituent of this aspect of the invention isdepicted as R⁷ and has been illustrated for the purposes of illustrationonly as phenyl, but other heteroaromatic monocyclic ring systems willalso be applicable. Typical R⁷ rings include phenyl, pyrrolyl,thiazolyl, pyridyl or pyrimidinyl. As elaborated below, the ring R⁷ andits linkage D′ constitutes a value for C₀-C₃Alkdiylcarbocyclyl,C₀-C₃Alkdiylheterocyclyl or —Z—ORb, where Rb is O₀—C₃Alkdiylcarbocyclyl,C₀-C₃Alkdiylheterocyclyl. Ring R⁷ is thus optionally substituted with 1to 3 substituents selected from halo, oxo, cyano, azido, nitro,C₁-C₄alkyl, Z—NRaRc, Z—O-Rc, Z—S—Rc, Z—C(═O)Rc, Z—(C═O)NRaRc,Z—NRaC(═O)Rc, Z—NRaSO_(p)Rc, Z—S(═O)_(p)Rc, Z—S(═O)_(p)NRaRc,Z—C(═O)ORc, Z—OC(═O)Rc, Z—NRaC(═O)ORc or Z—OC(═O)NRaRc.

Representative substituents for ring R⁷ include, for example one or twosubstituents selected from C₁-C₄alkyl, such as methyl, haloC₁-C₂alkyl,such as fluoromethyl and trifluoromethyl, —OC₁-C₃alkyl, such as methoxy,—C(═O)C₁-C₃alkyl, such as acetyl, or halo, such as fluoro.

The linkage to ring R⁷ is marked D′ in structure II and typicallycomprises a bond, methylene or ethylene linkage (i.e. R⁷ isC₀-C₃Alkdiylcarbocyclyl or C₀-C₃Alkdiylheterocyclyl as a substituent toR²) or an ether linkage (i.e. R⁷ is Z—O—Rb, where Z is a bond ormethylene, O is the ether linkage and Rb is C₀-C₃Alkdiylcarbocyclyl orC₀-C₃Alkdiylheterocyclyl). Further preferred structures for the linkageD′ include C(═O)CH₂ and CH₂C(═O).

Unless otherwise defined, the scientific and technological terms andnomenclature used in the foregoing and hereinafter have the same meaningas commonly understood by a person of ordinary skill to which thisinvention pertains, in addition, the following definitions apply unlessotherwise noted.

‘C₁-C₆alkyl’ (occasionally abbreviated to C₁-C₆alk and also used incompound expressions such as C₁-C₆alkyloxy etc) as applied herein ismeant to include straight and branched aliphatic carbon chainsubstituents containing from 1 to 6 carbon atoms, such as methyl, ethyl,n-propyl, isopropyl, n-butyl, isobutyl, t-butyl, pentyl, isopentyl,hexyl and any simple isomers thereof. Me denotes a methyl group.

‘C₁-C₄alkyl’ (occasionally abbreviated to O₁—C₄alk, and used incomposite expressions) as applied herein is meant to include methyl,ethyl, propyl, isopropyl, cyclopropyl, butyl, 1-methyl-cyclopropyl.

‘C₀-C₃alkanediyl’ as applied herein is meant to include a bond(C₀)bivalent straight and branched saturated carbon chains such asmethylene, ethanediyl, 1,3-propanediyl and 1,2-propanediyl.

‘C₀-C₃Alkdiyl’ as applied herein is meant to include a bond (C₀),bivalent C₁-C₃ straight and branched saturated carbon chains such asmethylene, ethanediyl, 1,3-propanediyl and 1,2-propanediyl, or C₂-C₃straight and branched unsaturated carbon chains such as ethenediyl,ethynediyl, 1,3-propenediyl and 1,2-propenediyl and propynediyl.

‘C₀-C₃alkanediyl-O—C₁-C₄alkyl’ (occasionally abbreviated toC₀-C₃alk-O—C₁-C₄alk) as applied herein is meant to include C₁-C₄alkoxygroups such as methoxy, ethoxy, n-propoxy, isopropoxy directly bonded(i.e. C₀) or through an intermediate methylene, ethanediyl,1,3-propanediyl or 1,2-propanediyl chain.

‘amide linkage’ as applied herein is meant to include —NRfC(═O)— and—C(═O)NRf— wherein Rf is C₁-C₄alkyl such as Me, or preferably H.

‘amine linkage’ as applied herein is meant to include —NH— or —NRe—,where Re is C₁-C₄alkyl or C(═O)C₁-C₄alkyl.

‘carbamate linkage’ as applied herein is meant to include —OC(C═O)NRf—and —NRfC(═O)O—, wherein Rf is C₁-C₄alkyl such as Me, or preferably H.

‘sulphonamide linkage’ as applied herein is meant to include —NRfS(═O)₂—and —S(═O)₂NRf— wherein Rf is C₁-C₄alkyl such as Me, or preferably H.

‘Amino’ is meant to include NH₂, and mono- and dialkylamino such asNHC₁-C₆alkyl and N(C₁-C₆alkyl)₂ groups especially NHC₁-C₃alkyl andN(C₁-C₃alkyl)₂, or the two alkyl groups of dialkylamino together form asaturated cyclic amine such as pyrrolidinyl, piperidinyl, piperazinyl,N-methylpiperazinyl and morpholinyl.

‘Amido’ is meant to include NHC(═O)C₁-C₆alkyl,NC₁-C₆alkylC(═O)C₁-C₆alkyl.

‘Carbamoyl’ is meant to include C(═O)NH₂, and mono- anddialkylcarbamoyl, such as C(═O)NHC₁-C₆alkyl and C(═O)N(C₁-C₆alkyl)₂,especially C(═O)NHC₁-C₃alkyl and C(═O)N(C₁-C₃alkyl)₂, or the twoC₁-C₆alkyl groups of the dialkylcarbamoyl together form a saturatedcyclic amine such as pyrrolidinyl, piperidinyl, piperazinyl andmorpholniyl.

‘Halo’ or halogen as applied herein is meant to include F, Cl, Br, I,particularly chloro and preferably fluoro.

Haloalkyl as applied herein means an alkyl in which 1-3 hydrogen atomsper carbon have been replaced with halo, preferably fluoro.Representative examples include difluoromethyl and 2,2-difluoroethyl,2,2,2-trifluoroethyl and 2-fluoroethyl. Preferred examples includetrifluoromethyl and fluoromethyl.

‘C₀-C₃alkanediylaryl’ as applied herein is meant to include a phenyl,naphthyl or phenyl fused to C₃-C₇cycloalkyl such as indanyl, which arylis directly bonded (i.e. C₀) or through an intermediate methylene,ethanediyl, 1,3-propanediyl or 1,2-propanediyl group as defined forC₀-C₃alkaneyl above. Unless otherwise indicated the aryl and/or itsfused cycloalkyl moiety is optionally substituted with 1-3 substituentsselected from halo, hydroxy, nitro, cyano, carboxy, C₁-C₆alkyl,C₁-C₄alkoxy, C₀-C₃alkanediylC₁-C₄alkoxy, C₁-C₄alkanoyl, amino, amido,carbamoyl, azido, oxo, mercapto, C₀-C₃alkanediylcarbocyclyl,C₀-C₃alkanediylheterocyclyl, it being understood that when thesubstituent is C₀-C₃alkanediylcarbocyclyl or C₀-C₃alkanediylheterocyclylsaid carbocyclyl or heterocyclyl is typically not further substitutedwith C₀-C₃alkanediylcarbocyclyl or C₀-C₃alkanediylheterocyclyl.“Aryl”has the corresponding meaning, i.e. where the C₀-C₃alkanediyl linkage isabsent.

‘C₀-C₃alkanediylcarbocyclyl’ as applied herein is meant to includeC₀-C₃alkanediylaryl and C₀-C₃alkanediylC₃-C₇cycloalkyl, andC₀-C₃alkanediylC₃-C₇cycloalkyl further comprising an additional fusedC₃-C₇cycloalkyl ring. Unless otherwise indicated the aryl or cycloalkylgroup is optionally substituted with 1-3 substituents selected fromhalo, hydroxy, nitro, cyano, carboxy, C₁-C₆alkyl, C₁-C₄alkoxy,C₀-C₃alkanediylC₁-C₄alkoxy, C₁-C₄alkanoyl, amino, amido, carbamoyl,azido, oxo, mercapto, C₀-C₃alkanediylcarbocyclyl andC₀-C₃alkanediylheterocyclyl, it being understood that when thesubstituent is C₀-C₃alkanediylcarbocyclyl or C₀-C₃alkanediylheterocyclylsaid carbocyclyl or heterocyclyl is typically not further substitutedwith C₀-C₃alkanediylcarbocyclyl or C₀-C₃alkanediylheterocyclyl.“Carbocyclyl” has the corresponding meaning, i.e. where theC₀-C₃alkanediyl linkage is absent.

‘C₀-C₃alkanediylheterocycylyl’ as applied herein is meant to include amono- or bicyclic, saturated or unsaturated, heteroatom-containing ringsystem, bonded directly i.e. (C₀), or through an intermediate methylene,ethanediyl, 1,3-propanediyl, or 1,2-propanediyl group as defined forC₀-C₃alkanediyl above. The ring system is derived by abstraction of ahydrogen from a monocyclic heteroatom containing ring such as pyrrole,furan, pyrroline, pyrrolidine, tetrahydrofuran, thiophene,tetrahydrothiophene, pyrrazole, imidazole, oxazole, isoxazole,pyrazoline, imidazoline, pyrazolidine, imidazolidine, dioxolane,thiazole, isothiazole, thiazolidine, isoxazolidine, 1,2,3-triazole,1,2,4-triazole, 1,2,3-oxadiazole, furazan, thiadiazole, tetrazole,pyridine, pyran, dihydropyran, piperidine, pyridazine, pyrimidine,pyrazine, piperazine, morpholine, dioxane, thiazine, thiomorpholine, orfrom a saturated or unsaturated, heteroatom-containing bicyclic ringsystem such as pyrrolizine, thienofurane, indole, isoindole, benzofuran,isobenzofuran, indoline, isoindoline, benzothiophene, isobenzothiophene,indazole, benzimidazole, benzthiazole, purine, quinoline, isoquinoline,4H-quinolizine, chromene, chromane, isochromane, cinnoline, quinazoline,quinoxazoline, naphtyridine, phtalazine, pteridine etc. Any suchnon-saturated ring system having an aromatic character may be referredto as heteroaryl herein. Unless otherwise indicated the hetero ringsystem is optionally substituted with 1-3 substituents selected fromhalo, hydroxy, nitro, cyano, carboxy, C₁-C₆alkyl, C₁-C₄alkoxy,C₀-C₃alkanediylC₁-C₄alkoxy, C₁-C₄alkanoyl, amino, amido, carbamoyl,azido, oxo, mercapto, C₀-C₃alkanediylcarbocyclyl,C₀-C₃alkanediylheterocyclyl, it being understood that when thesubstituent is C₀-C₃alkanediylcarbocyclyl or C₀-C₃alkanediylheterocyclylsaid carbocyclyl or heterocyclyl is typically not further substitutedwith C₀-C₃alkanediylcarbocyclyl or C₀-C₃alkanediylheterocyclyl.“Heterocyclyl” and “Heteroaryl” has the corresponding meaning, i.e.where the C₀-C₃alkanediyl linkage is absent.

Typically the terms ‘optionally substituted C₀-C₃alkanediylcarbocyclyl’and ‘optionally substituted C₀-C₃alkanediylheterocyclyl’ referspreferably to substitution of the carbocyclic or heterocyclic ring.

Typically heterocyclyl and carbocyclyl groups are thus a monocyclic ringwith 5 or especially 6 ring atoms, or a bicyclic ring structurecomprising a 6 membered ring fused to a 4, 5 or 6 membered ring.

Typical such groups include C₃-C₈cycloalkyl, phenyl, benzyl,tetrahydronaphthyl, indenyl, indanyl, heterocyclyl such as fromazepanyl, azocanyl, pyrrolidinyl, piperidinyl, morpholinyl,thiomorpholinyl, piperazinyl, indolinyl, pyranyl, tetrahydropyranyl,tetrahydrothiopyranyl, thiopyranyl, furanyl, tetrahydrofuranyl, thienyl,pyrrolyl, oxazolyl, isoxazolyl, thiazolyl, imidazolyl, pyridyl,pyrimidinyl, pyrazinyl, pyridazinyl, tetrazolyl, pyrazolyl, indolyl,benzofuranyl, benzothienyl, benzimidazolyl, benzthiazolyl, benzoxazolyl,benzisoxazolyl, quinolinyl, tetrahydroquinolinyl, isoquinolinyl,tetrahydroisoquinolinyl, quinazolinyl, tetrahydroquinazolinyl andquinoxalinyl, any of which may be optionally substituted as definedherein.

The saturated heterocycle thus includes radicals such as pyrrolinyl,pyrrolidinyl, pyrazolinyl, pyrazolidinyl, piperidinyl, morpholinyl,thiomorpholinyl, pyranyl, thiopyranyl, piperazinyl, indolinyl,azetidinyl, tetrahydropyranyl, tetrahydrothiopyranyl, tetrahydrofuranyl,hexahydropyrimidinyl, hexahydropyridazinyl,1,4,5,6-tetrahydropyrimidinylamine, dihydro-oxazolyl,1,2-thiazinanyl-1,1-dioxide, 1,2,6-thiadiazinanyl-1,1-dioxide,isothiazolidinyl-1,1-dioxide and imidazolidinyl-2,4-dione, whereas theunsaturated heterocycle include radicals with an aromatic character suchas furanyl, thienyl, pyrrolyl, oxazolyl, thiazolyl, imidazolyl,pyrazolyl, isoxazolyl, isothiazolyl, oxadiazolyl, triazolyl, tetrazolyl,thiadiazolyl, pyridinyl, pyridazinyl, pyrimidinyl, pyrazinyl,indolizinyl, indolyl, isoindolyl. In each case the heterocycle may becondensed with a phenyl or carbocyclyl ring to form a bicyclic ringsystem.

It should be noted that the radical positions on any molecular moietyused in the definitions may be anywhere on such a moiety as long as itis chemically stable.

Radicals used in the definitions of the variables include all possibleisomers unless otherwise indicated. For instance pyridyl includes2-pyridyl, 3-pyridyl and 4-pyridyl; pentyl includes 1-pentyl, 2-pentyland 3-pentyl.

When any variable occurs more than one time in any constituent, eachdefinition is independent.

The invention relates to the compounds of formula (I) per se, theprodrugs, N-oxides, addition salts, quaternary amines, metal complexes,and stereochemically isomeric forms thereof.

The invention further relates to methods for the preparation of thecompounds of formula (I), the prodrugs, N-oxides, addition salts,quaternary amines, metal complexes, and stereochemically isomeric formsthereof, its intermediates, and the use of the intermediates in thepreparation of the compounds of formula (I).

It will be appreciated that the compounds according to the invention maycontain one or more asymmetrically substituted carbon atoms. Thepresence of one or more of these asymmetric centres (chiral centres) incompounds according to the invention can give rise to stereoisomers, andin each case the invention is to be understood to extend to all suchstereoisomers, including enantiomers and diastereomers, and mixturesincluding racemic mixtures thereof. Racemates may be separated intoindividual optically active forms using known procedures (cf. AdvancedOrganic Chemistry: 3rd Edition: author J March, pp 104-107) includingfor example the formation of diastereomeric derivatives havingconvenient optically active auxiliary species followed by separation andthen cleavage of the auxiliary species.

Where optically active centres exist in the compounds of the invention,we disclose all individual optically active forms and combinations ofthese as individual specific embodiments of the invention, as well astheir corresponding racemates.

Where tautomers exist in the compounds of the invention, we disclose allindividual tautomeric forms and combinations of these as individualspecific embodiments of the invention. The compounds of the inventionmay be provided as pharmaceutically acceptable salts, solvates,prodrugs, N-oxides, quaternary amines, metal complexes, orstereochemically isomeric forms. These include acid addition salts suchas hydrochloride, hydrobromide, citrate, tosylate and maleate salts andsalts formed with phosphoric and sulphuric acid. In another aspectsuitable salts are base salts such as an alkali metal salt for examplesodium or potassium, an alkaline earth metal salt for example calcium ormagnesium, or organic amine salt for example triethylamine. Examples ofsolvates include hydrates.

The compounds of formula (I) have activity as pharmaceuticals. Aspreviously outlined the compounds of the invention are metalloproteinaseinhibitors, in particular they are inhibitors of MMP-12 and may be usedin the treatment of diseases or conditions mediated by MMP-12 such asasthma, rhinitis, chronic obstructive pulmonary diseases (COPD),arthritis (such as rheumatoid arthritis and osteoarthritis),atherosclerosis and restenosis, cancer, invasion and metastasis,diseases involving tissue destruction, loosening of hip jointreplacements, periodontal disease, fibrotic disease, infarction andheart disease, liver and renal fibrosis, endometriosis, diseases relatedto the weakening of the extracellular matrix, heart failure, aorticaneurysms, CNS related diseases such as Alzheimer's disease and MultipleSclerosis (MS), psoriasis and hematological disorders.

The compounds of the invention typically show a favourable selectivityprofile. Whilst we do not wish to be bound by theoreticalconsiderations, the compounds of the invention are believed to showselective inhibition for any one of the above indications relative toany MMP-1 inhibitory activity, by way of non-limiting example they mayshow in excess of 100 fold selectivity over any MMP-1 inhibitoryactivity.

Accordingly, the present invention provides a compound of formula (I),or a pharmaceutically acceptable salt, a solvate, prodrug, N-oxide,quaternary amine, metal complex, or stereochemically isomeric formthereof, as hereinbefore defined for use in therapy. In another aspect,the invention provides the use of a compound of formula (I), or apharmaceutically acceptable salt, a solvate, prodrug, N-oxide,quaternary amine, metal complex, or stereochemically isomeric formthereof, as hereinbefore defined in the manufacture of a medicament foruse in therapy.

In the context of the present specification, the term “therapy” alsoincludes “prophylaxis” unless there are specific indications to thecontrary. The terms “therapeutic” and as “therapeutically” should beconstrued accordingly.

The invention further provides a method of treating a disease orcondition mediated by MMP-12 which comprises administering to a patienta therapeutically effective amount of a compound of formula (I) or apharmaceutically acceptable salt, a solvate, prodrug, N-oxide,quaternary amine, metal complex, or stereochemically isomeric formthereof, as hereinbefore defined.

The invention also provides a method of treating an obstructive airwaysdisease (e.g. asthma or COPD) which comprises administering to a patienta therapeutically effective amount of a compound of formula (I) or apharmaceutically acceptable salt or solvate thereof as hereinbeforedefined.

For the above-mentioned therapeutic uses the dosage administered will,of course, vary with the compound employed, the mode of administration,the treatment desired and the disorder indicated. The daily dosage ofthe compound of formula I/salt/solvate (active ingredient) may be in therange from 0.001 mg/kg to 75 mg/kg, in particular from 0.5 mg/kg to 30mg/kg. This daily dose may be given in divided doses as necessary.Typically unit dosage forms will contain about 1 mg to 500 mg of acompound of this invention.

The compounds of formula (I) and pharmaceutically acceptable salts,solvates, prodrugs, N-oxides, quaternary amines, metal complexes, orstereochemically isomeric forms thereof may be used on their own butwill generally be administered in the form of a pharmaceuticalcomposition in which the formula (I) compound/salt/solvate (activeingredient) is in association with a pharmaceutically acceptableadjuvant, diluent or carrier. Depending on the mode of administration,the pharmaceutical composition will preferably comprise from 0.05 to 99%w (percent by weight), more preferably from 0.10 to 70% w, of activeingredient, and, from 1 to 99.95% w, more preferably from 30 to 99.90%w, of a pharmaceutically acceptable adjuvant, diluent or carrier, allpercentages by weight being based on total composition. A representativetablet within the scope of the pharmaceutical composition of theinvention could have a mass of 500-1500 mg with a loading of activeingredient in the range 35-75%, with the balance being excipients, suchas binders, disintegrants, antioxidants and the like.

Thus, the present invention also provides a pharmaceutical compositioncomprising a compound of formula (I) or a pharmaceutically acceptablesalt or solvate thereof as hereinbefore defined in association with apharmaceutically acceptable adjuvant, diluent or carrier. The inventionfurther provides a process for the preparation of a pharmaceuticalcomposition of the invention which comprises mixing a compound offormula (I) or a pharmaceutically acceptable salt or, a solvate,prodrug, N-oxide, quaternary amine, metal complex, or stereochemicallyisomeric form, thereof as hereinbefore defined with a pharmaceuticallyacceptable adjuvant, diluent or carrier.

The pharmaceutical compositions of this invention may be administered instandard manner for the disease or condition that it is desired totreat, for example by oral, topical, parenteral, buccal, nasal, vaginalor rectal administration or by inhalation. For these purposes thecompounds of this invention may be formulated by means known in the artinto the form of, for example, tablets, capsules, aqueous or oilysolutions, suspensions, emulsions, creams, ointments, gels, nasalsprays, suppositories, finely divided powders or is aerosols forinhalation, and for parenteral use (including intravenous, intramuscularor infusion) sterile aqueous or oily solutions or suspensions or sterileemulsions.

The inhaled (including aerosol & nebulised) route is convenient,especially for compounds of formula I with a rapid metabolism. A largenumber of appropriate devices able to dose and entrain thepharmaceutical active and deliver it to the lungs of the patient are nowavailable, even for COPD patients with a reduced respiratory capacity.See for example Byron's review in Proc. Am. Thorac. Soc. 2004:1(4)321-328 or Caprioti's review in Medsurg. Nurs.2005: 14(3) 185-194.

The oral delivery route, particularly capsules or tablets is favoured,especially for advanced COPD patients with severely compromisedrespiratory capacity.

In addition to the compounds of the present invention the pharmaceuticalcomposition of this invention may also contain, or be co-administered(simultaneously or sequentially) with, one or more pharmacologicalagents of value in treating one or more diseases or conditions referredto hereinabove. A representative example is inhaled steroids such as areconventionally used in asthma, for example budesonide and “Symbicort”(trade mark).

A general route to compounds according to the present invention whereinX and Y are both 0 is shown in scheme 1.

Coupling of two amino acids(1a) and (1b) carrying the appropriate sidechains, R¹ and (CR⁵R^(5′))_(n)D(CR⁶R^(6′))_(m)R², by standard peptidecoupling conditions like using couplings agents such as HOBt and EDCI orthe like in the presence of a base such as DIEA, NaHCO₃ or the like in asolvent like DMF provides the dipeptide (1c). The hydantoin derivative(1e) can then be achieved by removal of the Boc group according toconventional procedures such as treatment with an acid for instance TFAor formic acid or the like in a solvent like dichloromethane, followedby formylation of the formed primary amine with a formylating agent suchas phenyl chloroformate or phosgene or the like in the presence of abase like DIEA or NaHCO₃ and finally ring closure of the dipeptideeffected for example by treatment of the afforded formyl derivative (1d)with a base such as DIEA or the like and subsequent hydrolysis of themethyl ester by treatment with an acid such as HCl. If an alkylsubstituent, R³ on the secondary nitrogen of the hydantoin ring isdesired, this alkylation is conveniently performed subsequent to thering closure of compound 1d and prior to the ester hydrolysis, byreaction with a desired alkylating agent such as R³-Lg, wherein Lg is aleaving group such as a halide like a chloride, bromide or iodide or Lgis a derivative of sulphonic acid such as a triflate, tosylate mesylateor the like, optionally in the presence of a base such as t-BuOK.Coupling of hydroxylamine hydrochloride or a suitably protectedhydroxylamine, for example, O-tritylhydroxylamine orO-bensylhydroxylamine using standard peptide coupling conditions such asusing coupling agents like BOP and NMM in a solvent like DMF or asdescribed above or by using any other convenient reagents, provides thehydroxamic acid derivative (1f). The free acid (1g) is then achievedafter removal of the optional hydroxy protecting group carried out byusing the appropriate conditions according to the protecting group, suchas by acidic treatment in the case of a trityl protecting group.

Amino acids carrying the appropriate side chains for use in scheme 1 arecommercially available or they can be prepared by the skilled personaccording to literature procedures. For example, amino acids carrying aside chain containing a thioether, amine, ether or carbamate groupsuitable for the preparation of compounds of general formula I wherein Dis a thioether, amine, ether or amide linkage respectively, can beprepared from suitably protected, commercially available α-hydroxyalkylamino acids as illustrated in scheme 2.

The hydroxy group of amino acid (2a) can be converted to a thioether,amine or ether function for instance by way of a Mitsunobu reaction,i.e. reaction of the hydroxy group of the alcohol (2a) with anazodicarboxylate such as DIAD or the like in the presence oftriphenylphosphine or the like followed by displacement with a desiredthiol, amine or alcohol to provide the thioether derivative (2b), theamine (2c) or the ether (2d) respectively. A big variety of thiols,amines and alcohols are available commercially or in the literature. Analternative method to obtain the amine derivative (2c) is to oxidize thehydroxy group of the alcohol (2a) to the corresponding aldehyde,effected for example by treatment with Dess-Martin periodinane or by anyother suitable oxidation reagent, followed by a reductive amination withthe desired amino derivative R²(CH₂)_(m)NH₂. Ether derivatives (2d) canalternatively be achieved by alkylation of the hydroxy group of thealcohol (2a) by a displacement reaction with a suitable alkylating agentR²-Lg, where Lg is a leaving group such as a trichloroimidate, a halidelike a chloride, bromide or iodide, or a derivative of sulphonic acidsuch as a mesylate, triflate, tosylate or the like, in the presence of abase such as sodium hydride, Ag₂O, t.BuOK or the like in a solvent likeDMF or THF or the like. Amino acids carrying a carbamate containing sidechain can be prepared by reaction of amino acid (2a) with a suitableisocyanate R²N═C═O in the presence of a base like t.BuOK in a solventlike DMF or THF. Alternatively, compounds carrying a carbamatecontaining side chain can be prepared by reacting the hydroxy group ofthe amino acid (2a) with a formylating agent such phosgene or a suitablechlorocarbamate in the presence of a base like sodium hydrogen carbonatein a solvent like dichloromethane or toluene, followed by reaction witha desired amine R²—(CH₂)_(m)NH₂. Derivatives substituted with the groupsR⁴, R⁵, R^(5′), R⁶ and/or R^(6′), can be prepared according to the abovedescribed method by using the appropriately substituted amino acids andalkylating agents.

Amino acids carrying an amide, carbamate, urea or sulponamide containingside chain, i.e. D is an amide, carbamate urea or sulpnonamide linkagerespectively in compound (1b), can be prepared from α-aminoalkyl aminoacids as illustrated in scheme 3. α-Aminoalkyl amino acids arecommercially available or they can be prepared from the correspondingα-hydroxyalkyl amino acids according to literature procedures.

Reaction of the α-aminoalkyl amino acid (3a) with an appropriate acidchloride R²(CH₂)_(m)(C═O)Cl in a solvent like pyridine ordichloromethane optionally in the presence of a base like4-dimethylaminopuridine or the like provides the amide (3b), reaction ofthe amine (3a) with a desired chloroformate R²(CH₂)_(m)O(C═O)Cl providesthe carbamate (3c), whereas formylation of the amine (3a) using aconvenient formylating agent for instance phosgene,p-nitrochloroformate, CD or the like optionally in the presence of abase such as sodium hydrogen carbonate followed by reaction with thedesired amino derivative NH₂(CH₂)_(m)R² provides the urea (3d) andfinally, sulphonamides (3e) are obtained by reaction of the amine (3a)with a suitable sulphonyl chloride R²(CH₂)_(m)(S═O)₂Cl in a solvent likepyridine or dichloromethane optionally in the presence of a base like4-dimethylaminopyridine. Secondary amines may also be achieved from theprimary amine (3a) by alkylation of the nitrogen using any suitablealkylating agent such as an alkyl halide or an alkyl derivative ofsulphonic acid as described above. Derivatives substituted with thegroups R⁴, R⁵, R^(5′), R⁶ and/or R^(6′), can be prepared according tothe above described method by using the appropriately substituted aminoacids and alkylating, acylating, sulphonylating or aminating agents.

Amino acids (1b) used in scheme 1 carrying a saturated or unsaturatedall carbon side chain suitable for the preparation of compoundsaccording to general formula I wherein D is absent and R² is acarbocyclic or heterocyclic aromatic system, are commercially availableor they can be prepared from suitably protected α-amino-ω-hydroxy acidsor the corresponding α-amino-w-carboxy acids. An example is shown inscheme 3A.

The acid (3Aa) which is available commercially or in the literature, canbe reduced to the corresponding alcohol (3Ab) by any suitable methodknown in the field of synthetic organic chemistry, for example the acidcan be transformed to a suitable ester or acid halide like theN-hydroxysuccinimide followed by treatment with a reducing agent such asLiBH₄. The afforded alcohol (3Ab) can then be further reacted withiodine in the presence of triphenylphosphine and imidazole to providethe iodo derivative (3Ac). Conversion of the iodo derivative to thecorresponding zink derivative by reaction with zink activated with1,2-dibromoethane and chlorotrimethylsilane followed by a palladiumcatalyzed displacement reaction with a desired aryl iodide derivative,using for example tris(dibenzylideneacetone)palladium(0) as catalyst inthe presence of a phosphine ligand like tri(o-tolyl)phosphine, gives thearylated amino acid (3Ad). Removal of the Boc group, coupling of anamino acid, ring closure, hydrolysis of the benzyl ester andintroduction of the hydroxylamine moiety as described in scheme 1 givesthe hydantoin derivative (3Ae).

Amino acids containing an α,β-unsaturated all carbon side chain usefulfor the preparation of compounds according to general formula I whereinR⁴ and R⁵ together form an olefinic bond, can be prepared for example asshown in scheme 3B.

Oxidation of the alcohol (3Ab) using an oxidizing agent such as DessMartin periodinate to the corresponding aldehyde followed by a Grignardreaction or the like of with a desired Grignard reagent, R²(CH₂)_(m)MgBrprovides the hydroxy derivative (3Ba). Dehydration effected for instanceby acidic treatment provides the unsaturated compound (3Bb) whichsubsequently can be treated as described in scheme 1 to give the desiredhydantoin derivative (3Bc). The same strategy can also be applied inorder to obtain compounds with other side chains such as alternativeposition of the olefinic bond or heteroatom containing side chains bychoosing the appropriate hydroxyalkyl substituted amino acid andGrignard reagent.

Compounds containing a substituted R² moiety can be achieved by using anamino acid (1b) carrying the desired R²-substituent in scheme 1, or thesubstituent can be introduced at a later stage of the synthesis. Whenthe substituent is linked to R² by a carbon-carbon bond, it isconveniently introduced by a palladium catalyzed coupling reaction.Scheme 3C illustrates a method employing a Suzuki coupling.

Coupling of the dipeptide (3Ca) with the boronic acid derivativeR⁷B(OH)₂ of the desired substituent in the presence of a palladiumcatalyst such as Pd(PPh₃)₂Cl₂ or the like and a base like sodiumcarbonate provides the R⁷-substituted dipeptide (3Cb). Removal of theBoc group, coupling of an amino acid, ring closure, hydrolysis of thebenzyl ester and introduction of the hydroxylamine moiety as describedin scheme 1 gives the hydantoin derivative (3Cc). Other palladiumcatalyzed coupling reactions known from the literature may alternativelybe used for the introduction of a carbon linked substituent to R². Forinstance, a Heck coupling reaction wherein a desired activated alkene iscoupled to an aromatic or vinylic R² moiety using a catalyst such asPd(OAc)₂ or the like in the presence of a base such as triethylamine orpotassium carbonate or the like provides alkene substituted compounds.

Although the method in scheme 3C is illustrated with a bromobenzene ringas R² group it should be understood that the same strategy is applicableto other R² groups such as substituted and unsubstituted carbocycles andheterocycles.

An alternative strategy for the preparation of the compounds of theinvention is to first prepare a suitable hydantoin derivative andsubsequently elongate the side chain and thus introduce the desiredlinkage D. Hydantoin derivatives carrying a hydroxyalkyl or aminoalkylside chain whereto the various functional groups can be attached aresuitable intermediates for this strategy. An example of theirpreparation is illustrated in scheme 4.

The hydantoin derivative (4c) can be prepared from the two amino acids(4a) and (4b) as described in scheme 1. Removal of the benzyl group forexample by catalytic hydrogenation using a catalyst such as palladium oncarbon optionally in the presence of a base like sodium hydrogencarbonate and in the case of R³ being hydrogen, protection of the ringnitrogen with any suitable amino protecting group such as a boc groupusing standard methods well known in the art, gives the hydroxyalkylderivative (4d). The corresponding aminoalkyl derivative (4e) can thenbe prepared by conversion of the hydroxy group to an amino group forexample by transforming the hydroxy group to a leaving group such as amesylate or the like by treatment with mesylchloride in a solvent likepyridine optionally in the presence of a base such as triethylaminefollowed by displacement of the leaving group with azide and finallyreduction of the azide to an amine by any suitable reduction method suchas treatment with Ph₃P. Derivatives substituted with the groups R⁴, R⁵and/or R^(5′) can be prepared according to the above described method byusing the appropriately substituted amino acid instead of theunsubstituted amino acid (4b).

Subsequent elongation of the hydroxyalkyl side chain in order to obtaina thioether, amine, ether or carbamate containing side chain can beperformed as illustrated in scheme 5.

The hydroxy group of the hydantoin (4d) can be converted to a thioether,amine or ether function for instance by way of a Mitsunobu reaction,i.e. reaction of the hydroxy group of the alcohol (4d) with anazodicarboxylate such as DIAD or the like in the presence oftriphenylphosphine or the like followed by displacement with a desiredthiol, amine or alcohol to provide the thioether, amine or the etherderivative respectively. A big variety of thiols, amines and alcoholsare available commercially or in the literature. An alternative methodto obtain amine derivatives, i.e. D′ is NH, is to oxidize the hydroxygroup of the alcohol (4d) to the corresponding aldehyde, effected forexample by treatment with Dess-Martin periodinane or by any othersuitable oxidation reagent, followed by a reductive amination with thedesired amino derivative R²(CH₂)_(m)NH₂. Ether derivatives, i.e. D′ isO, can alternatively be achieved by alkylation of the hydroxy group ofthe alcohol (4d) by a displacement reaction with a suitable alkylatingagent R²-Lg, where Lg is a leaving group such as a trichloroimidate or ahalide like a chloride, bromide or iodide, or a derivative of sulphonicacid such as a mesylate, triflate, tosylate or the like, in the presenceof a base such as sodium hydride, Ag₂O t.BuOK or the like in a solventlike DMF or THF or the like. Amino acids carrying a carbamate containingside chain can be prepared by reaction of hydantoin (4d) with a suitableisocyanate R²(CH₂)_(m)N═C═O in the presence of a base like t.BuOK in asolvent like DMF or THF. Alternatively, compounds carrying a carbamatecontaining side chain can be prepared by reacting the hydroxy group ofthe hydantoin (4d) with a formylating agent such phosgene in thepresence of a base like sodium hydrogen carbonate in a solvent likedichloromethane or toluene, followed by reaction with a desired amineR²(CH₂)_(m)NH₂.

Hydantoins carrying an amide, carbamate, urea or sulphonamide containingside chain, i.e. D is an amide, carbamate, urea or sulphonamide linkagerespectively in general formula (I), can be prepared from α-aminoalkylamino acids (4e) as illustrated in scheme 6.

Reaction of the α-aminoalkyl hydantoin (4e) with an appropriate acidchloride R²(CH₂)_(m)(C═O)Cl in a solvent like pyridine ordichloromethane optionally in the presence of a base like4-dimethylaminopyridine or the like provides the amide (6a), reactionwith a desired chloroformate R²(CH₂)_(m)O(C═O)Cl provides the carbamate(6b) whereas formylation of the amine (4e) using a convenientformylating agent, for instance phosgene, p-nitrochloroformate, CDI orthe like optionally in the presence of a base such as sodium hydrogencarbonate followed by reaction with the desired amino derivativeNH₂(CH₂)_(m)R² provides the urea (6c) and finally, sulpnonamides (6d)are obtained by reaction of the amine (4e) with a suitable sulphonylchloride R²(CH₂)_(m)(S═O)₂Cl in a solvent like pyridine ordichloromethane optionally in the presence of a base like4-dimethylaminopuridine. Secondary amines, i.e. D is an amino linkage ingeneral formula I, may also be prepared from the primary amine (4e) byalkylation of the nitrogen using any suitable alkylating agent such asan alkyl halide or an alkyl derivative of sulphonic acid as describedabove. Removal of the protecting groups, boc and trityl, by standardmethods such as acidic treatment then provides the unprotectedhydroxamic acids. Derivatives substituted with the groups R⁴, R⁵,R^(5′), R⁶ and/or R^(6′), can be prepared according to the abovedescribed method by using the appropriately substituted amino acid andacylating, sulphonylating or aminating agents.

Compounds according to the present invention wherein one or both of thecarbonyl groups of the hydantoin moiety is replaced by thiocarbonyl areconveniently prepared from thiopeptides. Various methods for thepreparation of thiopeptides are described in the literature and oneexample, described by R. Michelot et al. in Bioorganic & MedicinalChemistry Vol. 4, No 12 1996 p. 2201-2209, is shown in Scheme 7.

The amino thioacid (7a) can be achieved from the corresponding aminoacid (2b, 2c, 2d or 2e) by activation of the amino acid withisobutylchloroformate and N-methylmorpholine in a solvent like THFfollowed by treatment with H₂₅ and subsequent acidifying with forinstance HCl. Coupling of the afforded amino thioacid with a natural orunnatural amino acid (7b) under standard peptide coupling conditionssuch as using a coupling reagent like BOP-CI or PyBOP or the like in thepresence of a base such as DIEA or the like in a solvent like THFprovides the thiodipeptide (7c).

Alternatively, the thiodipeptide (7c) can be achieved from the aminoacid (2b, 2c, 2d or 2e) by converting the acid function to a nitrile byusing for instance a reagent like trimethylsilanecarbonitrile in thepresence of a Lewsis acid such as BF₃—OEt₂ followed by treatment asdescribed by C. H. Williams et al. in J. Chem. Soc. Perkin Trans. I,1988, p. 1051-1055 and finally coupling of the second amino acid (7b) asdescribed above.

A further alternative to the thiodipeptide (7c) is by conversion of thedipeptide (1c) by using the thionation reagent2,4-bis(4-methoxyphenyl)-1,2,3,4-dithiadiphosphetane 2,4-disulfidedescribed by K. Clausen et al. in Tetrahedron, Vol. 37, 1981, p.3635-3639.

Amino thioacids substituted with the groups R⁴, R⁵, R^(5′), R⁶ and/orR^(6′), can be prepared according to the above described methods bystarting from the appropriately substituted compounds corresponding toamino acids (2b-2e) carrying the desired substituents.

A thiohydantoin derivative can then be formed by taking thethiodipeptide (7c) through the steps described for the dipeptide (1c) inscheme 1. An example is shown in scheme 8.

Removal of the Boc group from thiodipeptide (8a) by treatment with anacid for instance TFA or formic acid in a solvent like dichloromethane,followed by formylation of the formed primary amine with a formylatingagent such as phenyl chloroformate or phosgene or the like in thepresence of a base like DIEA or NaHCO₃ yields the carbamate (8b). Ringclosure of the thiodipeptide effected for example by treatment with abase such as DIEA or the like and subsequent hydrolysis of the methylester by treatment with an acid such as HCl gives the carboxylic acid(8c). Coupling of hydroxylamine hydrochloride or a suitably protectedhydroxylamine, for example, O-tritylhydroxylamine orO-bensylhydroxylamine using standard peptide coupling conditions such asusing coupling reagents like BOP and NMM in a solvent like DMF or asdescribed above or any other convenient reagents, provides thehydroxamic acid (8c). The free acid (8e) is then achieved after removalof the optional hydroxy protecting group carried out by using theappropriate conditions according to the protecting group, such as byacidic treatment in the case of a trityl protecting group.

Scheme 9 illustrates a method to prepare compounds according to generalformula I wherein Y is S and X is O or S.

Removal of the Boc group from thiodipeptide (9a), prepared as describedin scheme 1 or 7, by treatment with an acid for instance TFA or formicacid or the like in a solvent like dichloromethane, followed by ringclosure effected for example by reaction with thiocarbonyl diimidazoleor the like provides the hydantoin derivative (9b). Subsequenthydrolysis of the methyl ester by treatment with an acid such as HClgives the carboxylic acid (9c). Coupling of hydroxylamine hydrochlorideor a suitably protected hydroxylamine, for example,O-tritylhydroxylamine or O-bensylhydroxylamine using standard peptidecoupling conditions such as using coupling reagents like BOP and NMM ina solvent like DMF or as described above or any other convenientreagents, provides the hydroxamic acid (9d). The free acid (9e) is thenachieved after removal of the optional hydroxy protecting group carriedout by using the appropriate conditions according to the protectinggroup, such as by acidic treatment in the case of a trityl protectinggroup.

It will be readily apparent that the above described methods are notlimited to the stereochemistries indicated. The same methods are alsoapplicable to reactants having other sterochemistries and to racemates,the obtained product will have the configuration corresponding to theone of the reactants.

Any functional groups present on any of the constituent compounds usedin the preparation of the compounds of the invention are appropriatelyprotected where necessary. For example functionalities on the natural ornon-natural amino acids are typically protected as is appropriate inpeptide synthesis. Those skilled in the art will appreciate that theselection and use of appropriate protecting groups depend upon thereaction conditions. Suitable protecting groups are described in Greene,“Protective Groups in Organic Synthesis”, John Wiley & Sons, New York(1981) and “The Peptides: Analysis, Synthesis, Biology”, Vol. 3,Academic Press, New York (1981), the disclosure of which are herebyincorporated by reference.

DETAILED DESCRIPTION

Various embodiments of the compounds of the invention and keyintermediates towards such compounds will now be described by way ofillustration only with reference to the accompanying non-limitingchemistry and biology examples.

Method A

Example 1 Step a

2-(2-Tert-butoxycarbonylamino-4-phenyl-butyrylamino)-3-methylbutyricacid methyl ester (1a)

To an ice-cooled solution of D-valine methyl ester hydrochloride (1000mg, 3.58 mmol) and HOBt (in DMF (14 mL) was added EDCI (755 mg, 3.94mmol). After the mixture was stirred for 30 min,N-boc-L-homophenylalanine (600 mg, 3.58 mmol) and N-methylmorpholine (1mL, 8.95 mmol) were added. The mixture was warmed to room temperatureand stirred overnight. The solvent was removed and the residue waspartitioned between water and EtOAc. The aqueous layer was extractedwith EtOAc and the combined organic phases were dried over anhydrousNa₂SO₄. After concentration under reduced pressure, the crude titlecompound (2000 mg) was obtained and used in the next step withoutfurther purification.

Step b 2-(2-Amino-4-phenyl-butyrylamino)-3-methylbutyric acid methylester (1b)

To a solution of the crude compound obtained in step a above (2000 mg)in CH₂Cl₂ (10 mL) was added TFA(10 mL). After stirring for 1.5 h at roomtemperature, the mixture was concentrated. The residue was diluted withEtOAc whereafter 10% NaOH was added to adjust the pH to 14. The aqueouslayer was extracted with EtOAc and the combined organic phases weredried over anhydrous Na₂SO₄. After concentration under reduced pressure,the crude title product (1400 mg) was obtained for next step withoutfurther purification.

Step c

3-Methyl-2-(2-phenoxycarbonylamino-4-phenyl-butyrylamino)-butyric acidmethyl ester (1c)

To a mixture of the crude compound obtained in step b above (1400 mg) indioxane (18 mL) and water (2 mL) was added phenyl chloroformate (0.9 mL,7.16 mmol) and DIEA (1.6 mL, 8.95 mmol). The mixture was stirred at roomtemperature for 3 h and concentrated under reduced pressure. The residuewas partitioned between water and EtOAc. The aqueous layer was extractedwith EtOAc, the combined organic phases were dried and concentrated. Theresidue was purified by silica gel column chromatography to afford thetitle compound as a white solid (1165 mg, 79% yield, three steps).

¹H NMR (300 MHz, CDCl₃): δ 0.89 (d, J=6.6 Hz, 3H); 0.94 (d, J=6.6 Hz,3H); 2.00-2.35 (m, 3H); 2.70-2.80 (m, 2H); 3.73 (s, 3H); 4.30-4.45 (m,1H); 4.30-4.45 (m, 1H); 4.57 (dd, J=8.1, 9.0 Hz, 1H); 5.84 (d, J=8.1Hz,1H); 5.84 (d, J=8.1Hz, 1H); 6.65 (d, J=9.0 Hz, 1H); 7.10-7.40 (m, 10H).

Step d

2-(2,5-Dioxo-4-phenethyl-imidazolidin-1-yl-3-methyl-butyric acid methylester (1d)

To a solution of the compound obtained in step c above (1140 mg) in DMF(14 mL) was added DIEA (0.6 mL, 3.30 mmol). After stirring overnight atroom temperature, the solvent was removed. The residue was diluted withEtOAc and washed with water. The organic layer was dried andconcentrated under reduced pressure. The residue was purified by silicagel column chromatography to afford the title compound as a colourlessoil (672 mg, 77%).

¹H NMR (300 MHz, CDCl₃): δ 0.92 (d, J=6.9 Hz, 3H); 1.12 (d, J=6.9 Hz,3H); 1.95-2.35 (m, 2H); 2.60-2.85 (m, 3H); 3.71 (s, 3H); 4.00-4.10 (m,1H); 4.35 (d, J=8.4 Hz, 1H); 7.00 (s, 1H); 7.10-7.35 (m, 5H).

Step e

2-(2,5-Dioxo-4-phenethyl-imidazolidin-1-yl-3-methyl-butyric acid (1e)

A mixture of the compound obtained in step d above (482 mg, 1.52 mmol)and 6 N HCl (20 mL) was stirred at 70° C. for 3 h. The reaction mixturewas cooled to room temperature and extracted with CH₂Cl₂. The combinedorganic phases were washed with brine, dried and concentrated. Theresidue was purified by silica gel column chromatography to afford thetitle compound as a colorless oil (210 mg, 46% yield) with a recover ofstarting material (200 mg).

¹H NMR (300 MHz, CD₃OD): δ 0.86 (d, J=6.8 Hz, 3H); 1.01 (d, J=6.8 Hz,3H); 1.94-2.20 (m, 2H); 2.50-2.80 (m, 3H); 4.10-4.15 (m, 1H); 4.27 (d,J=8.4 Hz, 1H); 7.10-7.30 (m, 5H).

Step f2-(2,5-Dioxo-4-phenethyl-imidazolidin-1-yl-N-hydroxy-3-methyl-butyramide(1f)

To a solution of the compound obtained in step e above (109 mg, 0.36mmol) in DMF (1.8 mL) was added BOP (190 mg, 0.43 mmol) at 0° C. Afterstirring for 30 min, HONH₂xHCl (50 mg, 11.38 mmol) andN-methylmorpholine (0.16 mL, 1.44 mmol) were added. The mixture waswarmed to room temperature and stirred overnight. The solvent wasremoved and the residue was partitioned between EtOAc and a saturatedsolution of NH₄Cl. The aqueous layer was extracted with EtOAc, dried andconcentrated. The residue was purified by silica gel columnchromatography to afford the title compound as a white solid (63 mg, 55%yield).

¹H NMR (300 MHz, CD₃OD): δ0.89 (d, J=6.8 Hz, 3H); 1.01 (d, J=6.8 Hz,3H); 1.94-2.20 (m, 2H); 2.60-2.80 (m, 2H); 2.80-3.00 (s, 1H); 4.00-4.10(m, 2H); 7.10-7.30 (m, 5H).

Example 2

2-(2,5-Dioxo-4-phenethyl-imidazolidin-1-yl-N-hydroxy-propionamide (2)

The procedure described in method A was followed but using D-alaninemethyl ester hydrochloride instead of D-valine methyl esterhydrochloride which gave the title compound (8 mg)

¹H NMR (300 MHz, CD₃OD): δ 1.56 (dd, J=2.7, 7.2 Hz, 3H), 1.90-2.20 (m,2H), 2.72 (dd, J=7.8, 7.8 Hz, 2H), 4.00-4.15 (m, 1H), 4.60-4.15 (m, 1H),7.10-7.35 (m, 5H).

Example 4

3-Cyclohexyl-2-(2,5-dioxo-4-phenethyl-imidazolidin-1-yl-N-hydroxy-propionamide(4)

The procedure described method A was followed but usingD-cyclohexyl-alanine methyl ester hydrochloride instead of D-valinemethyl ester hydrochloride which gave the title compound (3 mg).

¹H NMR (300 MHz, CDCl₃): δ 0.80-2.10 (m, 16H), 2.72 (s, 2H), 4.09 (s,1H), 4.70-4.75 (m, 1H), 6.98 (s, 1H), 7.10-7.35 (m, 5H), 10.06 (s, 1H).

Example 5

2-[4-(2-Biphenyl-4-yl-ethyl)-2,5-dioxo-imidazolidin-1-yl]-N-hydroxy-3-methyl-butyramide(5)

The procedure described method A was followed but using4-biphenyl-4-yl-2-tert-butoxycarbonylamino-butyric acid instead ofN-boc-L-homophenylalanine, which gave the title compound (6 mg).

¹H NMR (300 MHz, CDCl₃): δ0.84 (d, J=6.0 Hz, 3H), 1.03 (d, J=6.0 Hz,3H), 1.94-2.30 (m, 2H), 2.50-2.80 (m, 3H), 4.10-4.15 (m, 1H), 4.25 (d,J=11.4 Hz, 1H), 6.30-6.50 (m, 1H), 7.10-7.60 (m, 9H), 10.10 (s, 1H).

Example 6

2-[2,5-Dioxo-4-(3-phenylpropyl)-imidazolidin-1-yl]-N-hydroxy-3-methyl-butyramide(6)

The procedure described method A was followed but using2-tert-butoxycarbonylamino-5-phenyl-pentanoic acid instead ofN-boc-L-homophenylalanine, which gave the title compound (8 mg).

¹H NMR (300 MHz, CDCl₃): δ 0.93 (d, J=6.6 Hz, 3H), 1.03 (d, J=6.6 Hz,3H), 1.90-2.10 (m, 4H), 2.55-2.85 (m, 3H), 4.00-4.15 (m, 1H), 4.27 (d,J=11.4 Hz, 1H), 6.30 (s, 1H), 7.15-7.35 (m, 5H), 8.12 (s, 1H).

Example 72-(2,5-Dioxo-4-phenethyl-imidazolidin-1-yl)-N-hydroxy-3-methyl-butyramide(7)

The procedure described method A was followed but usingN-boc-D-homophenylalanine instead of N-boc-L-homophenylalanine, whichgave the title compound (10 mg).

¹H NMR (300 MHz, CDCl₃): δ 0.83 (d, J=6.6 Hz, 3H), 1.03 (d, J=6.6 Hz,3H), 1.90-2.10 (m, 1H), 2.20-2.30 (m, 1H), 2.60-2.80 (m, 3H), 4.00-4.20(m, 1H), 4.27 (d, J=11.4 Hz, 1H), 6.30 (s, 1H), 7.15-7.40 (m, 5H), 8.12(s, 1H).

Example 8N-Hydroxy-3-methyl-2-[4-(2-naphtalen-1-yl-ethyl)-(2,5-dioxo-imidazolidin-1-yl)-butyramide(8)

The procedure described method A was followed but using2-tert-butoxycarbonylamino-4-naphtalen-1-yl-butyric acid instead ofN-boc-L-homophenylalanine, which gave the title compound (20 mg).

¹H NMR (300 MHz, CDCl₃): δ 0.85 (d, J=6.6 Hz, 3H), 1.04 (d, J=6.6 Hz,3H), 2.00-2.30 (m, 2H), 2.50-2.70 (m, 1H), 3.10-3.30 (m, 2H), 4.10-4.25(m, 1H), 4.29 (d, J=11.1Hz, 1H), 6.03 (s, 1H), 7.10-8.00 (m, 9H), 10.10(s, 1H).

Example 9

2-(2,5-Dioxo-4-phenethyl-imidazolidin-1-yl)-N-hydroxy-3-methyl-butyramide(9)

The procedure described method A was followed but using L-valine methylester hydrochloride instead of D-valine methyl ester hydrochloride,which gave the title compound (15 mg).

¹H NMR (300 MHz, CD₃OD): δ 0.88 (d, J=6.4 Hz, 3H), 1.02 (d, J=6.5 Hz,3H), 1.97-1.92 (m, 1H), 2.11-2.06 (m, 1H), 2.72-2.67 (m, 2H), 2.92-2.86(m, 1H), 4.10-4.03 (m, 2H), 7.30-7.18 (m, 5H).

Example 10

2-(2,5-Dioxo-4-phenethyl-imidazolidin-1-yl)-N-hydroxy-3-phenhyl-propionamide(10)

The procedure described method A was followed but using D-phenylalaninemethyl ester hydrochloride instead of D-valine methyl esterhydrochloride, which gave the title compound (3 mg).

¹H NMR (300 MHz, CD₃OD): δ 1.64-1.61 (m, 1H), 1.95-1.91 (m, 1H),2.49-2.45 (m, 2H), 3.42-3.39 (m, 2H), 3.93-3.85 (m, 1H), 4.97-4.90 (m,1H), 6.90-6.75 (m, 1H), 7.26-7.00 (m, 10H).

Example 11

2-Cyclohexyl-2-(2,5-dioxo-4-phenethyl-imidazolidin-1-yl)-N-hydroxy-acetamide(11)

The procedure described method A was followed but usingD-cyclohexylglycine methyl ester hydrochloride instead of D-valinemethyl ester hydrochloride, which gave the title compound (4 mg).

¹H NMR (300 MHz, CDCl₃): δ 1.49-0.84 (m, 6H), 1.81-1.66 (m, 4H),2.06-1.96 (m, 1H), 2.38-2.23 (m, 2H), 2.80-2.76 (m, 2H), 4.11-3.99 (m,1H), 4.32-4.28 (m, 1H), 6.79 (s, 1H), 7.34-7.20 (m, 5H).

Example 12

2-(2,5-Dioxo-4-phenethyl-imidazolidin-1-yl)-N-hydroxy-3,3-dimethyl-butyramide(12)

The procedure described method A was followed but usingD-tert.butylglycine methyl ester hydrochloride instead of D-valinemethyl ester hydrochloride, which gave the title compound (2 mg).

¹H NMR (300 MHz, CD₃OD): δ 1.11 (s, 9H), 2.01-1.89 (m, 1H), 2.18-2.07(m, 1H), 2.75-2.70 (m, 2H), 4.05 (dd, J₁=6.9 Hz, 4.1₂=2.1Hz, 1H), 4.41(s, 1H), 7.30-7.15 (m, 5H).

Method B

Example 13 Step a

2-Tert-butoxycarbonylamino-3-hydroxy-propionic acid methyl ester (13a)

To a solution of L-serine methyl ester hydrochloride (10.00 g, 64.5mmol) and Boc₂O (28.12 g, 129 mmol) in THF (258 mL) was slowly addedEt₃N (27 mL, 194 mmol) at room temperature. The reaction was stirredovernight, then quenched with saturated NaHCO₃ and brine, concentratedunder vacuum and diluted with CH₂Cl₂ and brine. The mixtures wereseparated and the aqueous layers were extracted with CH₂Cl₂ three times,the combined organic phases were washed with brine, dried andconcentrated, the residue was purified by silica gel columnchromatography which gave the title compound as colourless oil (14.147g, 86% yield).

Step b

O-(4-bromo)-benzyl-boc-L-serine methyl ester (13b)

A solution of 1-bromo-4-(bromomethyl)benzene (7.5 g, 30.24 mmol) in Et₂O(60 ml) was added to a mixture of the compound obtained in step a above(2.27 g, 10.30 mmol) and Ag₂O (7.007 g, 30.24 mmol) in Et₂O (400 ml) atroom temperature. After being stirred for 4 days, the reaction mixturewas filtered through celite and washed with CH₂Cl₂, concentrated undervacuum to give crude product. The crude product was purified by silicagel column chromatography to give the title compound as colourless oil(2.567 g, 64%).

Step c

O-(4-bromo)-benzyl-boc-L-serine (13c)

To a solution of O-(4-bromo)-benzyl-boc-L-serine (13b) (2567 mg, 6.633mmol.) in THF (40 mL) was added a solution of LiOH (238 mg, 9.95 mmol)in water (10 mL) at 0° C., the reaction was stirred for 5 h. 0.5 N HClwas added to neutralize, the mixture was then concentrated under vacuum.The residue was diluted with EtOAc and washed with brine. The combinedorganic layers were dried and concentrated; the crude product waspurified by silica gel column chromatography which gave the titlecompound as colourless oil (2330 mg, 91%).

Step d

2-[3-(4-Bromobenzyloxy)-2-tert-butoxycarbonylamino]-3-methylbutyric acidmethyl ester (13d)

To a mixture of the compound obtained in step c above (2.330 g, 6.25mmol), NMM (1.5 mL, 13.4 mmol) and HOBt (1.433 g, 10.62 mmol) in DMF (15mL) at −15° C. was added EDCI (1.017 g, 6.87 mmol). After the reactionwas stirred for 30 minutes, it was allowed to warm to room temperature,(R)-methyl 2-amino-3-methylbutanoate hydrochloride (1.147 g, 6.87 mmol)was then added and the reaction was stirred overnight. The solvent wasremoved under vacuum; the residue was diluted with EtOAc and washed withbrine. The combined organic layers were dried and concentrated; thecrude product was purified by silica gel column chromatography whichgave the title compound as colourless oil (2.246 g, 74%).

Step e

2-[4-(4-Bromobenzyloxymethyl)-2,5-dioxo-imidazolidin-1-yl]-3-methyl-butyricacid methyl ester (13e)

The compound obtained in step d above (1246 mg, 2.56 mmol) was stirredin TFA (5 mL) at 0° C. for 5 h, then concentrated under vacuum. Theresidue was diluted with CH₂Cl₂, washed with saturated NaHCO₃ and brine,dried over anhydrous Na₂SO₄, concentrated to give crude product. Theobtained crude product was stirred in dioxane (9 mL) and water (1 mL) at0° C., DIEA (990 mg, 7.68 mmol) and phenyl chloroformate (479 mg, 3.07mmol) were added and the mixture was stirred for 2 h. The solvent wasremoved under vacuum; the residue was diluted with EtOAc and washed withbrine. The combined organic layers were dried and concentrated to giveyellow oil. The obtained oil was then stirred with DIEA (990 mg, 7.68mmol) in DMF (10 mL) for 24 h. After general workup, the crude productwas purified by silica gel column chromatography which gave the titlecompound as colourless oil (623 mg, 59%).

Step f

2-[4-(4-Bromobenzyloxymethyl)-2,5-dioxo-imidazolidin-1-yl]-3-methyl-butyricacid (13f)

A mixture of the compound obtained in step e above (623 mg, 1.512 mmol)and 2 N HCl (20 mL) was refluxed for 2 h. The reaction mixture wascooled down and then extracted with EtOAc. The combined organic layerswere dried and concentrated; the crude product was purified by silicagel column chromatography which gave the title compound as colourlessoil (409 mg, 68%).

Step q

N-Benzyloxy-2-[4-(4-bromobenzyloxymethyl)-2,5-dioxo-imidazolidin-1-yl]-3-methyl-butyramide(13g)

To a mixture of the compound obtained in step f above (409 mg, 1.020mmol), NMM (0.4 mL, 3.58 mmol) and HOBt (234 mg, 1.734 mmol) in DMF (10mL) at −15° C. was added EDCI (214 mg, 1.123 mmol). After the reactionwas stirred for 30 minutes, it was allowed to warm to room temperature,BnONH₂HCl (179 mg, 1.123 mmol) was then added and the reaction wasstirred overnight. The solvent was removed under vacuum; the residue wasdiluted with EtOAc and washed with brine. The combined organic layerswere dried and concentrated; the crude product was purified by silicagel column chromatography which gave the title compound as an oil (426mg, 83% yield).

Step h

2-[4-(4-Bromobenzyloxymethyl)-2,5-dioxo-imidazolidin-1-yl]-N-hydroxy-3-methyl-butyramide(13h)

The oil obtained in step g above and 10% Pd/C (42 mg) were stirred inMeOH (15 mL) at room temperature for 2 h under H₂ atmosphere, themixture was filtered through celite, washed with MeOH for several timesand then concentrated. The residue was purified by silica gel columnchromatography which gave the title compound as an oil (217 mg, 62%yield).

¹H NMR (300 MHz, CD₃OD): δ 0.79 (d, J=6.6 Hz, 3H), 0.97 (d, J=6.6 Hz,3H), 2.79-2.95 (m, 1H), 3.71-3.78 (m, 1H), 3.84-3.92 (m, 1H), 4.02 (d,J=10.8 Hz, 1H), 4.18-4.22 (m, 1H), 4.61 (s, 2H), 7.48 (d, J=8.4 Hz, 2H),7.62 (d, J=8.4 Hz, 2H).

Example 14

2-[2,5-Dioxo-4-(4-trifluoromethyl-bezyloxymethyl)-imidazolidin-1-yl]-N-hydroxy-3-methyl-butyramide(14)

The procedure described in method B was followed, but using4-(trifluoromethyl)benzyl bromide instead of 4-bromobenzyl bromide,which gave the title compound (10 mg).

¹H-NMR (300 Hz, CD₃OD): δ 0.80 (m, 3H), 0.98 (m, 3H), 2.87 (m, 1H), 3.74(m, 1H), 3.88 (m, 1H), 4.00 (m, 1H), 4.21, (m, 1H), 4.61, (m, 2H),7.64-7.47 (m, 5H).

Example 152-[4-(3-Fluorobenzyloxymethyl)-2,5-dioxo-imidazolidin-1-yl]-N-hydroxy-3-methyl-butyramide(15)

The procedure described in method B was followed, but using3-fluorobenzyl bromide instead of 4-bromobenzyl bromide, which gave thetitle compound (16 mg).

¹H-NMR (300 Hz, CD₃OD): δ 0.80 (m, 3H), 0.98 (m, 3H), 2.87 (m, 1H), 3.72(m, 1H), 3.85 (m, 1H), 4.01 (m, 1H), 4.19, (m, 1H), 4.55, (m, 2H),7.40-6.96 (m, 4H).

Example 162-[4-(2-Fluorobenzyloxymethyl)-2,5-dioxo-imidazolidin-1-yl]-N-hydroxy-3-methyl-butyramide(16)

The procedure described in method B was followed, but using2-fluorobenzyl bromide instead of 4-bromobenzyl bromide, which gave thetitle compound (21 mg).

¹H-NMR (300 Hz, CD₃OD): δ 0.77 (m, 3H), 0.96 (m, 3H), 3.30 (m, 1H), 3.75(m, 1H), 3.84 (m, 1H), 4.18 (m, 1H), 4.60, (m, 2H), 7.37-7.05 (m, 4H).

Example 17

2-[4-(4-Fluorobenzyloxymethyl)-2,5-dioxo-imidazolidin-1-yl]-N-hydroxy-3-methyl-butyramide(15)

The procedure described in method B was followed, but using4-fluorobenzyl bromideinstead of 4-bromobenzyl bromide, which gave thetitle compound (9 mg).

¹H-NMR (300 Hz, CD₃OD): δ 0.78 (m, 3H), 0.93 (m, 3H), 2.82 (m, 1H), 3.72(m, 1H), 3.84 (m, 1H), 4.06 (m, 1H), 4.18, (m, 1H), 4.52, (m, 2H),7.12-7.03 (m, 2H), 7.38-7.29 (m, 2H).

Example 182-[2,5-Dioxo-4-(3-trifluoromethyl-bezyloxymethyl)-imidazolidin-1-yl]-N-hydroxy-3-methyl-butyramide(18)

The procedure described in method B was followed, but using3-(trifluoromethyl)benzyl bromide instead of 4-bromobenzyl bromide,which gave the title compound (14 mg).

¹H-NMR (300 Hz, CD₃OD): δ 0.76 (m, 3H), 0.96 (m, 3H), 2.84 (m, 1H), 3.77(m, 1H), 3.87 (m, 1H), 4.00 (m, 1H), 4.21, (m, 1H), 4.60, (m, 2H),7.60-7.54 (m, 4H).

Example 192-(4-Benzyloxymethyl-2,5-dioxo-imidazolidin-1-yl)-N-hydroxy-3-methyl-butyramide(19)

The procedure described in method B was followed, but using benzylbromide instead of 4-bromobenzyl bromide, which gave the title compound(11 mg).

¹H-NMR (300 Hz, CDCl₃): δ 0.83 (d, J=6.6 Hz, 3H), 1.04 (d, J=6.6 Hz,3H), 2.61 (m, 1H), 3.75 (m, 2H), 4.22 (m, 1H), 4.32 (d, J=11.4 Hz, 1H),4.54 (m, 2H), 7.34 (m, 5H).

Method C

Example 20 Step a

2-[2-tert-Butoxycarbonylamino-3-(3′-fluorobiphenyl-4-ylmethoxy)-propionylamino]-3-methylbutyricacid methyl ester (20a)

A mixture of the compound obtained in Example 13, step d (948 mg, 1.951mmol), Pd (PPh₃)₂Cl₂ (136 mg, 0.1951 mmol) and 3-fluorophenylboronicacid (328 mg, 2.341 mmol) in toluene (10 mL) were stirred under anatmosphere of argon at room temperature. A solution of 2 M Na₂CO₃aqueous (4 mL) was added and the reaction were heated to reflux for 5 h.After cooling, the reaction was diluted with EtOAc and brine, theaqueous layer was extracted with EtOAc, and the combined organic layerswere dried over anhydrous NaSO₄ and concentrated. The residue waspurified by silica gel column chromatography to give the title compoundas a white solid (813 mg, 83%).

Step b

2-[4-(3′-Fluorobiphenyl-4-ylmethoxymethyl)-2,5-dioxo-imidazolidin-1-yl-3-methyl-butyricacid methyl ester (20b)

The compound obtained in step a above (20a) (813 mg, 1.619 mmol) wasstirred in TFA (4 mL) at 0° C. for 5 h, then concentrated under vacuum.The residue was diluted with CH₂Cl₂, washed with saturated NaHCO₃ andbrine, dried over anhydrous Na₂SO₄ and concentrated which gave the crudeproduct. The obtained crude product was stirred in dioxane (9 mL) andwater (1 mL) at 0° C. DIEA (610 mg, 4.86 mmol) and phenyl chloroformate(379 mg, 2.429 mmol) were added, and the mixture was stirred for 2 h.The solvent was removed under vacuum; the residue was diluted with EtOAcand washed with brine. The combined organic layers were dried andconcentrated to give a yellow oil. The obtained oil was then stirredwith DIEA (610 mg, 4.86 mmol) in DMF (10 mL) for 24 h. After generalworkup, the crude product was purified by silica gel columnchromatography which gave the title compound as a white solid (374 mg,54% yield).

Step c

2-[4-(3′-Fluorobiphenyl-4-ylmethoxymethyl)-2,5-dioxo-imidazolidin-1-yl-3-methyl-butyricacid (20c)

A mixture of the compound obtained in step b above (20b) (374 mg, 0.874mmol) and 2 N HCl (15 mL) was refluxed for 2 h. The reaction mixture wascooled down and then extracted with EtOAc. The combined organic layerwas dried and concentrated; the crude product was purified by silica gelcolumn chromatography to give the title compound as colorless oil (166mg, 46%).

Step d

2-[4-(3′-Fluorobiphenyl-4-ylmethoxymethyl)-2,5-dioxo-imidazolidin-1-yl-N-hydroxy-3-methyl-butyramide(20d)

To a solution of the compound obtained in step c above (20c) (166 mg,0.401 mmol) in DMF (5 mL) was added BOP reagent (213 mg, 0.481 mmol) at0° C. After stirring for 30 min, HONH₂xHCl (50 mg, 11.38 mmol) andN-methylmorpholine (0.15 mL, 1.34 mmol) were added. The mixture waswarmed to room temperature and stirred overnight. The solvent wasremoved and the residue was partitioned between EtOAc and saturatedNH₄Cl solution. The aqueous layer was extracted with EtOAc, the organiclayer was dried and concentrated. The residue was purified by silica gelcolumn chromatography to afford the title compound as a white solid (60mg, 35%).

¹H-NMR (300 Hz, CD₃OD): 0.82 (d, J=6.6 Hz, 3H), 0.97 (d, J=6.3 Hz, 3H),2.82 (m, 1H), 3.76 (m, 1H), 3.84 (m, 1H), 4.03 (m, 1H), 4.20, (m, 1H),4.58, (m, 2H), 7.61-7.58 (m, 3H), 7.45-7.37 (m, 5H).

Example 21

2-[2,5-Dioxo-4-(4′-trifluoromethylbiphenyl-4-ylmethoxymethyl)-imidazolidin-1-yl-N-hydroxy-3-methyl-butyramide(21)

The procedure described in method C was followed, but using4-(trifluoromethyl)phenylboronic acid instead of 3-fluorophenylboronicacid, which gave the title compound (6 mg).

¹H-NMR (300 Hz, CD₃OD): 0.82 (m, 3H), 0.96 (m, 3H), 2.82 (m, 1H), 3.72(m, 1H), 3.76 (m, 1H), 4.01 (m, 1H), 4.21, (m, 1H), 4.59, (m, 2H),7.43-7.40 (m, 2H), 7.82-7.64 (m, 4H).

Method D

Example 22 Step a

3-Hydroxy-2-(tritylamino)-propionic acid methyl ester (22a)

A solution of Et₃N (13.4 mL, 96.78 mmol) in CH₂Cl₂ (40 mL) was added toa solution of L-serine methyl ester hydrochloride (5.0 g, 32.26 mmol)and Ph₃CCl (13.5 g, 48.39 mmol) in CH₂Cl₂ (129 mL) at 0° C. under N₂atmosphere. The reaction was then allowed to warm to room temperatureand was stirred overnight. The reaction was quenched with saturatedNaHCO₃, the aqueous layer was extracted with CH₂Cl₂, and the combinedorganic layers were washed with brine, dried and concentrated, theresidue was purified by silica gel column chromatography which gave thetitle compound as a colourless solid (11.41 g, 98%).

Step b

3-(4-Bromophenoxy)-2-(tritylamino)-propionic acid methyl ester (22b)

Under N₂ atmosphere, to a solution of the solid obtained in step a above(4.17 g, 11.55 mmol), PPh₃ (3.72 g, 12.71 mmol) and 4-bromophenol (2.20g, 12.71 mmol) in toluene (25 mL) was slowly added a solution of DEAD(2.21 g, 12.71 mmol) in toluene (20%). The reaction mixture was heatedto 80° C. After being stirred for 3 days, the reaction was diluted withEtOAc, the organic layer was washed with 0.3 N HCl, saturated NaHCO₃ andbrine. The solvent was removed under vacuum, and the residue waspurified by silica gel column chromatography to give the title compound(4.41 g, 74%).

Step c

2-Amino-3-(4-bromophenoxy)-propionic acid methyl ester (22c)

The compound obtained in step b above (22b) (2.21 g, 4.10 mmol) wasstirred in TFA (8 mL) and CH₂Cl₂ (10 mL) at 0° C.→rt for 1 h, thesolvent was removed under vacuum. MeOH (10 mL) was added and then NaHCO₃(344 mg, 4.10), the mixture was stirred at room temperature for 4 h andthen concentrated. The residue was dissolved in CH₂Cl₂ and washed withbrine, dried and concentrated to give crude title compound (1.07 g,91%).

Step d

3-(4-Bromophenoxy)-2-tert-butoxycarbonylamino-propionic acid methylester (22d)

The crude product obtained in step c above (22c) was dissolved in CH₂Cl₂(30 mL), a solution of Boc₂O (1.34 g, 6.15 mmol) in CH₂Cl₂ (10 mL) andEt₃N (1.15 mL, 8.20 mmol) was slowly added. After being stirred for 20h, the reaction was quenched with saturated NaHCO₃; the aqueous phasewas extracted with CH₂Cl₂. The combined organic layers were dried andconcentrated. The residue was purified by silica gel columnchromatography to give the title compound (1.32 g, 86% yield).

Step e

3-(4-Bromophenoxy)-2-tert-butoxycarbonylamino-propionic acid (22e)

To a solution of the compound obtained in step d above (22d) (1.087 g,2.91 mmol.) in THF (40 mL) at 0° C. was added a solution of LiOH H₂O(244 mg, 5.82 mmol) in water (10 mL). After being stirred for 6 h, 0.5 NHCl (5 mL) was added and the reaction was concentrated under vacuum. Theresidue was diluted with EtOAc and washed with brine. The combinedorganic layers were dried over Na₂SO₄ and concentrated; the residue waspurified by silica gel column chromatography to give the title compoundas a colourless oil (816 mg, 78% yield).

Step f

2-[3-(4-Bromophenoxy)-2-tert-butoxycarbonylamino-propionylamino]-3-methyl-butyricacid methyl ester (22f)

A solution of the compound obtained in step e above (22e) (816 mg, 2.27mmol), NMM (0.55 mL, 4.922 mmol) and HOBt (521 mg, 3.864 mmol) in DMF(10 mL) was stirred at 0° C. for 10 minutes, then the reaction wascooled to −15° C., and EDCI (478 mg, 2.497 mmol) was added. The reactionwas stirred for 30 minutes at −15° C. and then allowed to warm to roomtemperature, (R)-methyl 2-amino-3-methylbutanoate hydrochloride (417 mg,2.497 mmol) was added. After being stirred overnight, the reactionmixture was concentrated under vacuum; the residue was diluted withEtOAc and washed with brine. The combined organic layers were dried andconcentrated; the residue was purified by silica gel columnchromatography to give the title compound as colourless oil (900 mg,84%).

Step g

2-[4-(4-Bromophenoxymethyl)-2,5-dioxo-imidazolidin-1-yl]-3-methyl-butyricacid methyl ester (22g)

The compound obtained in step f above (22f) (900 mg, 1.907 mmol) wasstirred in TFA (8 mL) at 0° C. for 5 h, and then concentrated undervacuum. The residue was diluted with CH₂Cl₂, washed with saturatedNaHCO₃ and brine, dried over anhydrous Na₂SO₄, concentrated to give thecrude product. The obtained crude product was stirred in dioxane (9 mL)and water (1 mL) at 0° C., DIEA (737 mg, 5.72 mmol) and phenylchloroformate (446 mg, 2.861 mmol) were added, and the mixture wasstirred for 1.5 h. The solvent was removed under vacuum; the residue wasdiluted with EtOAc and washed with brine. The combined organic layerswere dried and concentrated to give a yellow oil. The obtained oil wasthen stirred with DIEA (737 mg, 5.72 mmol) in DMF (10 mL) for 24 h.After general workup, the crude product was purified by silica gelcolumn chromatography to give the title compound as colorless oil (245mg, 32% from step f).

Step h

2-[4-(4-Bromophenoxymethyl)-2,5-dioxo-imidazolidin-1-yl]-3-methyl-butyricacid (22h)

A mixture of the compound obtained in step g above (22g) (759 mg, 1.907mmol) and 3 N HCl (20 mL) was stirred at 80° C. for 2 h. The reactionmixture was cooled down and then extracted with EtOAc. The combinedorganic layers were dried and concentrated; the crude product waspurified by silica gel column chromatography which gave the titlecompound as colorless oil (300 mg, 41%).

Step i

N-benzyloxy-2-[4-(4-bromophenoxymethyl)-2,5-dioxo-imidazolidin-1-yl]-3-methylbutyramide(22i)

A solution of the compound obtained in step h above (22h) (300 mg, 0.782mmol), NMM (0.19 mL, 1.72 mmol) and HOBt (179 mg, 1.329 mmol) in DMF (11mL) were stirred at 0° C. for 10 minutes, then the reaction was cooledto −15° C., and EDCI (165 mg, 0.860 mmol) was added. The reaction wasstirred for 30 minutes at −15° C. and then allowed to warm to roomtemperature, BnONH₂HCl (137 mg, 0.860 mmol) was added. After beingstirred overnight, the reaction mixture was concentrated under vacuum,and the residue was diluted with EtOAc and washed with brine. Thecombined organic layers were dried and concentrated; the residue waspurified by silica gel column chromatography which gave the titlecompound as colorless oil (426 mg, 83% yield).

Step j

2-[4-(4-Bromophenoxymethyl)-2,5-dioxo-imidazolidin-1-yl]-N-hydroxy-3-methylbutyramide(22j)

The oil obtained in step i above (22i) (271 mg, 0.571 mmol)and 10% Pd/C(31 mg) were stirred in MeOH (25 mL) at room temperature for 3 h underH₂ atmosphere, the mixture was filtered through celite, washed with MeOHfor several times and then concentrated. The residue was purified bysilica gel column chromatography which gave the title compound as an oil(118 mg, 52% yield). % yield).

¹H NMR (300 MHz, CD₃OD): δ 0.95 (d, J=6.6 Hz, 3H), 1.02 (d, J=6.6 Hz,3H), 2.83-3.01 (m, 1H), 4.07 (d, J=10.8 Hz, 1H), 4.23-4.29 (dd, J₁=2.7Hz, J₂=13.5 Hz, 2H), 4.40 (s, 1H), 6.84 (d, J=9.3 Hz, 2H), 7.38 (d,J=9.3 Hz, 2H).

Example 23

2-(2,5-Dioxo-4-phenoxymethyl-imidazolidin-1-yl)-N-hydroxy-3-methyl-butyramide(23)

The procedure described in method D was followed, but using phenolinstead of 4-bromophenol, which gave the title compound (7 mg).

¹H-NMR (300 Hz, CD₃OD): 1.04-0.96 (m, 6H), 2.95 (m, 1H), 4.10 (m, 1H),4.29-4.24 (m, 21H), 4.40 (m, 1H), 7.28-6.87 (m, 5H).

Method E

Example 24 Step a

2-[2-tert-Butoxycarbonylamino-3-(4-phenyl-cyclohexa-1,5-dienyloxy)-propionylamino]-3-methylbutyricacid methyl ester (24a)

A solution of 2 M Na₂CO₃ (4 mL)was added at room temperature under anatmosphere of Argon to a mixture of the compound obtained in Example 22,step f (401 mg, 0.848 mmol), Pd(PPh₃)₂Cl₂ (154 mg, 0.22 mmol) andphenylboronic acid (145 mg, 1.1872 mmol) in toluene (10 mL) and thereaction was heated to reflux. After 5 h, the reaction was cooled toroom temperature. The mixture was diluted with EtOAc, and washed withbrine. The combined organic layers were dried over anhydrous NaSO₄ andconcentrated under vacuum. The residue was purified by silica gel columnchromatography which gave the title compound as a white solid (255 mg,64%).

Step b

2-[4-(Biphenyl-4-yloxymethyl)-(2,5-dioxo-imidazolidin-1-yl]-3-methyl-butyricacid methyl ester (24b)

The compound obtained in step a (24a) above (764 mg, 1.626 mmol) wasstirred in TFA (10 mL) at 0° C. for 5 h, then concentrated under vacuum.The residue was diluted with CH₂Cl₂, washed with saturated NaHCO₃ andbrine, dried over anhydrous Na₂SO₄ and concentrated which gave the crudeproduct. The obtained crude product was stirred in dioxane (9 mL) andwater (1 mL) at 0° C., DIEA (629 mg, 4.878 mmol) and phenylchloroformate (382 mg, 2.43 mmol) were added, and the mixture wasstirred for 2 h. The solvent was removed under vacuum; the residue wasdiluted with EtOAc and washed with brine. The combined organic layerswere dried and concentrated to give a yellow oil. The obtained oil wasthen stirred with DIEA (629 mg, 4.878 mmol) in DMF (10 mL) for 30 h.After general workup, the crude product was purified by silica gelcolumn chromatography which gave the title compound as colourless oil(328 mg, 51%).

Step c

2-[4-(Biphenyl-4-yloxymethyl)-(2,5-dioxo-imidazolidin-1-yl]-3-methyl-butyricacid (24c)

A mixture of the compound obtained in step b above (24b) (320 mg, 0.808mmol) and 3 N HCl (15 mL) was stirred at 80° C. for 4 h. The reactionmixture was cooled down and then extracted with EtOAc. The combinedorganic layers were dried and concentrated; the crude product waspurified by silica gel column chromatography which gave the titlecompound as colourless oil (96 mg, 31%).

Step d

N-Benzyloxy-2-[4-(biphenyl-4-yloxymethyl)-(2,5-dioxo-imidazolidin-1-yl]-3-methylbutyramide(24d)

A solution of the compound obtained in step c above (96 mg, 0.250 mmol),NMM (0.05 mL, 0.448 mmol) and HOBt (58 mg, 0.426 mmol) in DMF (6 mL)were stirred at 0° C. for 10 minutes, then the reaction was cooled to−15° C., and EDCI (53 mg, 0.275 mmol) was added. The reaction wasstirred for 30 minutes at −15° C. and then allowed to warm to roomtemperature, BnONH₂HCl (44 mg, 0.275 mmol) was added. After beingstirred overnight, the reaction mixture was concentrated under vacuum,the residue was diluted with EtOAc and washed with brine. The combinedorganic layers were dried and concentrated, the residue was purified bysilica gel column chromatography which gave the title compound ascolourless oil (92 mg, 76%).

Step e

2-[4-(Biphenyl-4-yloxymethyl)-(2,5-dioxo-imidazolidin-1-yl]-N-hydroxy-3-methylbutyramide(24e)

The oil obtained in step d above (24d) (90 mg, 0.185 mmol) and 10% Pd/C(12 mg) were stirred in MeOH (15 mL) at room temperature for 3 h underH₂ atmosphere. The mixture was filtered through celite, washed with MeOHseveral times and then concentrated. The residue was purified by silicagel column chromatography which gave the title compound as an oil (32mg, 44%).

¹H NMR (300 MHz, CD₃OD): δ 0.99 (d, J=6.6 Hz, 3H), 1.04 (d, J=6.6 Hz,3H), 2.82-2.98 (m, 1H), 4.11 (d, J=10.8 Hz, 1H), 4.25-4.40 (m, 2H), 4.43(s, 1H), 6.98 (d, 2H), 7.22-7.42 (m, 3H), 7.50-7.58 (m, 4H).

Method F

Example 25 Step a

2-Amino-6-benzoylamino-hexanoic acid (25a)

To a solution of L-lysine (1) (3.65 g, 0.02 mol) in water (50 mL) at 90°C. was added CuCO₃ (2.5 g) portionwise. After being refluxed for 40 min,the mixture was cooled and filtered. The filtrate was further cooled to0° C., and a solution of BzCl (3.5 mL, 0.03 mol) and NaOH (2.7 g, 0.0685mol) in water (20 mL) were added. The reaction was stirred at 0° C. for1 h and then allowed to warm to room temperature. After 2 days, thereaction mixture was filtered and the solid was washed with water andEt₂O. This obtained solid was then added to a solution of EDTA (7.0 g)in water (350 mL), the mixture was heated to reflux until the reactionsolution became clear blue. The reaction was cooled which gave a whiteprecipitate. This precipitate was collected and washed with water andEt₂O and dried which afforded the title compound as a white solid (1.8g, 36%).

Step b

6-Benzoylamino-2-tert-butoxycarbonylamino-hexanoic acid (25b)

To a solution of the compound obtained in step a above (1.0 g, 4.0 mmol)Et₃N (0.92 mL, 6.6 mmol) and dioxane/H₂O (1:1, v/v) (40 mL) at 0° C. wasadded Boc₂O (0.96 g, 4.4 mmol). The reaction was allowed to warm to roomtemperature and stirred overnight. The solvent was removed and theresidue was partitioned between water and EtOAc. The aqueous layer wasacidified and extracted with EtOAc, and the combined organic phases weredried over anhydrous Na₂SO₄. After concentration under vacuum, the crudetitle compound (1.4 g) was obtained and used in the next reactionwithout further purification.

Step c

6-Benzoylamino-2-tert-butoxycarbonylamino-hexanoylamino)-3-methyl-butyricacid methyl ester (25c)

EDCI (1.26 g, 6.6 mmol) was added at −15° C. to a mixture of thecompound obtained in step b above (25b) (1.0 g, 3.0 mmol), NaHCO₃ (0.83g, 9.8 mmol) and HOBt (1.15 g, 7.5 mmol) in DMF (30 mL). The reactionwas stirred for 30 minutes, and then it was allowed to warm to roomtemperature. (R)-Methyl 2-amino-3-methylbutanoate hydrochloride (0.58 g,3.3 mmol) was then added and the reaction was stirred overnight. Thesolvent was removed under vacuum; the residue was diluted with EtOAc andwashed with brine. The combined organic layers were dried andconcentrated; the crude product was purified by silica gel columnchromatography which gave the title compound as a white solid (1.1 g,79%).

Step d

2-(2-Amino-6-benzoylamino-hexanoylamino)-3-methyl-butyric acid methylester (25d)

A mixture of the compound obtained in step c above (1.0 g, 2.1 mmol) andHCO₂H (20 mL) in CHCl₃(15 mL) was stirred at room temperature overnight.The reaction was diluted with CH₂Cl₂ and NaHCO₃ was added to adjust thepH to 8. The organic layer was washed with brine, dried and concentratedto give crude title compound as a colorless oil (0.6 g, 78% yield).

Step e

2-[4-(Benzoylamino-butyl)-(2,5-dioxo-imidazolidin-1-yl]-3-methyl-butyricacid methyl ester (25e)

To a mixture of the crude compound obtained in step d above (25d) (0.6g, 1.65 mmol) in dioxane (18 mL) and water (2 mL) was added phenylchloroformate (0.21 mL, 1.65 mmol) and DIEA (0.6 mL, 3.3 mmol). Themixture was stirred at room temperature for 3 h and concentrated underreduced pressure. The residue was partitioned between water and EtOAc.The aqueous layer was extracted with EtOAc, the combined organic phaseswere dried and concentrated which gave a white solid (0.79 g). Thiswhite solid was dissolved in DMF (20 mL), and DIEA (0.28 mL, 1.6 mmol)was added. After stirring overnight at room temperature, the solvent wasremoved. The residue was diluted with EtOAc and washed with water. Theorganic layer was dried and concentrated under reduced pressure. Theresidue was purified by silica gel column chromatography which affordedthe title compound as a colorless oil (0.43 g, 69%).

Step f2-[4-(Benzoylamino-butyl)-(2,5-dioxo-imidazolidin-1-yl]-3-methyl-butyricacid (25f)

A mixture of the compound obtained in step e above (25f) (0.21 g, 0.54mmol) and 6 N HCl (5 mL) was heated at 70° C. for 6 h. The reaction wasdiluted with water and extracted with CH₂Cl₂. The organic layer waswashed with brine, dried over Na₂SO₄, and concentrated under vacuumwhich gave the title compound as a crude oil (0.2 g, 98%).

Step g

N-{4-[1-(1-Benzyloxycarbamoyl-2-methyl-propyl)-(2,5-dioxo-imidazolidin-4-yl]-butyl}-benzamide(25g)

A solution of the compound obtained in step f above (25f) (200 mg, 0.53mmol), NMM (0.15 mL, 1.3 mmol) and HOBt (98 mg, 0.64 mmol) in DMF (5 mL)was stirred at 0° C. for 15 minutes, then the reaction was cooled to−15° C., and EDCI (123 mg, 0.64 mmol) was added. The reaction wasstirred for 30 minutes at −15° C. and then allowed to warm to roomtemperature and BnONH₂HCl (102 mg, 0.64 mmol) was added. After beingstirred overnight, the reaction mixture was concentrated under vacuum;the residue was diluted with EtOAc and washed with brine. The combinedorganic layers were dried and concentrated, the residue was purified bysilica gel column chromatography which gave the title compound as awhite solid (150 mg, 59%).

Step h

N-{4-[1-(1-Hydroxycarbamoyl-2-methyl-propyl)-(2,5-dioxo-imidazolidin-4-yl]-butyl}-benzamide(25h)

The compound obtained in step g above (25g) (150 mg, 0.312 mmol) and 10%Pd/C (20 mg) were stirred in MeOH (10 mL) at room temperature for 15 hunder H₂ atmosphere, the mixture was filtered through celite, washedwith MeOH several times and then concentrated. The residue was purifiedby silica gel column chromatography which gave the title compound as awhite solid (50 mg, 41%).

¹H NMR (300 MHz, CD₃OD+CDCl₃): δ 0.86 (d, 3H, J=6.9 Hz,), 1.02 (d, 2H,J=6.9 Hz), 1.46-1.91 (m, 6H), 2.83-2.86 (m, 1H), 3.34-3.42 (m, 2H),4.04-4.08 (m, 2 H), 7.41-7.82 (m, 5H).

Example 26

2-{2,5-Dioxo-4-[2-(4-phenoxyphenyl)-ethyl]-imidazolidin-1-yl}-N-hydroxy-3-methyl-butyramide(26)

The procedure described in method A was followed but using2-tert-butoxycaronylamino-4-(4-phenyoxyphenyl)-butyric acid instead ofN-boc-homophenylalanine which gave the title compound (8 mg).

¹H NMR (300 MHz, CDCl₃): δ 0.82-1.02 (dd, J₁=6.3 Hz, J₂=53.4 Hz,6H),1.90-2.30 (m, 2H), 2.60-2.80 (m, 3H), 4.00-4.08 (m, 1H), 4.19-4.24(d, J=10.8 Hz, 1H), 6.59 (s, 1H), 6.91-6.99 (m, 4H), 7.05-7.4-0 (m, 5H).

Example 27 Preparation of Substituted N-Boc-L-HomophenylalanineDerivatives

Step a

A series of substituted homophenylalanine derivatives were synthesizedby coupling of the corresponding substituted aryl iodide to2-tert-butoxy-carbonylamino-4-iodobutyric acid according to theprocedure described in J. Org. Chem. 1998, 63, 7875.

Step b

To a solution of the compound obtained in step a above in 1,4-dioxanewas added 2N NaOH. After stirring at room temperature for 3 h, thereaction was diluted with EtOAc. The mixture was acidified by slowaddition of 1N HCl to PH 6, and then extracted with EtOAc. The organicphases were washed with brine, dried and concentrated. The residue waspurified by silica gel column chromatography to afford the acidderivatives 27a-27m.

Example 28

2-[2,5-Dioxo-4-(2-o-tolylethyl)-imidazolidin-1-yl]-N-hydroxy-3-methyl-butyramide(28)

The procedure described in method A was followed but using 27a insteadof N-boc-L-homophenylalanine which gave the title compound (8 mg).

¹H NMR (300 MHz, CDCl₃): δ 0.90 (d, J=6.6 Hz, 3H), 1.12 (d, J=6.6 Hz,3H), 1.91-2.03 (m, 1H), 2.07-2.23 (m, 1H), 2.29 (s, 3H), 2.60-2.80 (m,3H), 4.09-4.16 (m, 1H), 4.37 (d, J=8.7 Hz, 1H), 6.78 (s, 1H), 7.13 (m,4H).

Example 29

2-[2,5-Dioxo-4-(2-m-tolylethyl)-imidazolidin-1-yl]-N-hydroxy-3-methyl-butyramide(29)

The procedure described in method A was followed but using 27b insteadof N-boc-L-homophenylalanine which gave the title compound (13 mg).

¹H NMR (300 MHz, CDCl₃): δ 0.83 (d, J=6.6 Hz, 3H), 1.01 (d, J=6.6 Hz,3H), 1.90-2.01 (m, 1H), 2.21-2.29 (m, 1H), 2.32 (s, 3H), 2.62-2.76 (m,3H), 4.02-4.04 (m, 1H), 4.21 (d, J=11.4 Hz, 1H), 6.52 (s, 1H), 6.98-7.05(m, 3H), 7.17-7.27 (m, 1H), 8.32 (s, br, 1H), 10.11 (s, 1H).

Example 30

2-[2,5-Dioxo-4-(2-p-tolylethyl)-imidazolidin-1-yl]-N-hydroxy-3-methyl-butyramide(30)

The procedure described in method A was followed but using 27c insteadof N-boc-L-homophenylalanine which gave the title compound (12 mg).

¹H NMR (300 MHz, CD₃OD): δ 0.88 (d, J=6.6 Hz, 3H), 1.01 (d, J=6.6 Hz,3H), 1.86-1.93 (m, 1H), 2.04-2.09 (m, 1H), 2.28 (s, 3H), 2.66 (t, J=7.8Hz, 2H), 2.86-2.92 (m, 1H), 4.01-4.06 (m, 2H), 7.08 (s, 4H).

Example 31N-Hydroxy-2-{4-[2-(2-methoxyphenyl)-ethyl]-2,5-dioxo-imidazolidin-1-yl}-3-methyl-butyramide(31)

The procedure described in method A was followed but using 27d insteadof N-boc-L-homophenylalanine which gave the title compound (11 mg).

¹H NMR (300 MHz, CD₃OD): δ 0.89 (d, J=6.6 Hz, 3H), 1.04 (d, J=6.6 Hz,3H), 1.84-1.97 (m, 1H), 2.09-2.21 (m, 1H), 2.72-2.91 (m, 3H), 3.84 (s,3H), 3.97-4.01 (m, 1H), 4.08 (d, J=10.8 Hz, 1H), 6.87-6.91 (m, 2H),7.14-7.23 (m, 2H), 7.58 (s, 1H).

Example 32N-Hydroxy-2-{4-[2-(3-methoxyphenyl)-ethyl]-2,5-dioxoimidazolidin-1-yl}-3-methylbutyramide(32)

The procedure described in method A was followed but using 27e insteadof N-boc-L-homophenylalanine which gave the title compound (8 mg).

¹H NMR (300 MHz, CD₃OD): δ 0.91 (d, J=6.6 Hz, 3H), 1.04 (d, J=6.6 Hz,3H), 1.91-1.98 (m, 1H), 2.09-2.14 (m, 1H), 2.71 (t, J=8.1Hz, 2H),2.91-2.95 (m, 1H), 3.79 (s, 3H), 4.05-4.09 (m, 2H), 6.76-6.82 (m, 3H),7.18-7.23 (m, 1H).

Example 33

N-Hydroxy-2-{4-[2-(4-methoxyphenyl)-ethyl]-2,5-dioxoimidazolidin-1-yl}-3-methylbutyramide(33)

The procedure described in method A was followed but using 27f insteadof N-boc-L-homophenylalanine which gave the title compound (11 mg).

¹H NMR (300 MHz, CD₃OD): δ 0.91 (d, J=6.6 Hz, 3H), 1.04 (d, J=6.6 Hz,3H), 1.88-1.95 (m, 1H), 2.04-2.11 (m, 1H), 2.68 (t, J=8.1Hz, 2H),2.90-2.98 (m, 1H), 3.78 (s, 3H), 4.06-4.09 (m, 2H), 6.86 (d, J=8.1Hz,2H), 7.15 (d, J=8.1Hz, 2H).

Example 34

2-{4-[2-(4-Ethylphenyl)-ethyl]-2,5-dioxoimidazolidin-1-yl}-N-hydroxy-3-methyl-butyramide(34)

The procedure described in method A was followed but using 27g insteadof N-boc-L-homophenylalanine which gave the title compound (14 mg).

¹H NMR (300 MHz, CDCl₃): δ 0.82 (d, J=6.6 Hz, 3H), 1.00 (d, J=6.6 Hz,3H), 1.21 (t, J=7.5 Hz, 3H), 1.90-2.03 (m, 1H), 2.21-2.27 (m, 1H), 2.61(q, J=7.5 Hz, 2H), 2.68-2.76 (m, 3H), 4.03 (s, br, 1H), 4.22 (d, J=11.4Hz, 1H), 6.42 (s, 1H), 7.10-7.26 (m, 4H), 8.24 (s, br, 1H), 10.09 (s,br, 1H).

Example 35

2-{4-[2-(4-tert-Butylphenyl)-ethyl]-2,5-dioxoimidazolidin-1-yl}-N-hydroxy-3-methylbutyramid(35)

The procedure described in method A was followed but using 27h insteadof N-boc-L-homophenylalanine which gave the title compound (13 mg).

¹H NMR (300 MHz, CDCl₃): δ 0.82 (d, J=6.3 Hz, 3H), 1.00 (d, J=6.3 Hz,3H), 1.29 (s, 9H), 1.90-2.04 (m, 1H), 2.20 (m, 1H), 2.62-2.73 (m, 3H),4.05-4.10 (m, 1H), 4.18-4.28 (m, 1H), 6.64 (s, 1H), 7.12 (d, J=8.1Hz,2H), 7.31 (d, J=8.1Hz, 2H), 8.35 (s, br, 1H), 10.12 (s, br, 1H).

Example 36

2-{4-[2-(2-Fluorophenyl)-ethyl]-2,5-dioxoimidazolidin-1-yl}-N-hydroxy-3-methylbutyramide(36)

The procedure described in method A was followed but using 27i insteadof N-boc-L-homophenylalanine which gave the title compound (7 mg).

¹H NMR (300 MHz, CD₃OD): δ 0.91 (d, J=6.6 Hz, 3H), 1.04 (d, J=6.6 Hz,3H), 1.91-2.02 (m, 1H), 2.05-2.13 (m, 1H), 2.75-2.81 (m, 2H), 2.90-2.98(m, 1H), 4.06-4.13 (m, 2H), 7.03-7.14 (m, 2H), 7.21-7.29 (m, 2H).

Example 37

2-{4-[2-(3-Fluoro-phenyl)-ethyl]-2,5-dioxoimidazolidin-1-yl}-N-hydroxy-3-methylbutyramide(37)

The procedure described in method A was followed but using 27j insteadof N-boc-L-homophenylalanine which gave the title compound (15 mg).

¹H NMR (300 MHz, CD₃OD): δ 0.87 (d, J=6.9 Hz, 3H), 1.00 (d, J=6.9 Hz,3H), 1.88-1.96 (m, 1H), 2.06-2.10 (m, 1H), 2.71 (t, J=8.1Hz, 2H),2.86-2.92 (m, 1H), 4.01-4.06 (m, 2H), 6.87-7.03 (m, 3H), 7.24-7.29 (m,1H).

Example 38

2-{4-[2-(4-Fluoro-phenyl)-ethyl]-2,5-dioxoimidazolidin-1-yl}-N-hydroxy-3-methylbutyramide(38)

The procedure described in method A was followed but using 27k insteadof N-boc-L-homophenylalanine which gave the title compound (11 mg).

¹H NMR (300 MHz, CD₃OD): δ 0.88 (d, J=6.9 Hz, 3H), 1.01 (d, J=6.9 Hz,3H), 1.91-1.95 (m, 1H), 2.05-2.10 (m, 1H), 2.70 (t, J=7.8 Hz, 2H),2.89-2.93 (m, 1H), 4.03-4.06 (m, 2H), 6.97-7.03 (m, 2H), 7.20-7.24 (m,2H).

Example 39

2-{4-[2-(4-Benzylphenyl)-ethyl]-2,5-dioxoimidazolidin-1-yl}-N-hydroxy-3-methylbutyramide(39)

The procedure described in method A was followed but using 271 insteadof N-boc-L-homophenylalanine which gave the title compound (12 mg).

¹H NMR (300 MHz, CDCl₃): δ 0.82 (d, J=6.6 Hz, 3H), 1.01 (d, J=6.6 Hz,3H), 1.88-2.00 (m, 1H), 2.15-2.28 (m, 1H), 2.60-2.76 (m, 3H), 3.95 (s,2H), 4.00-4.04 (m, 1H), 4.22 (d, J=11.7 Hz, 1H), 6.23 (s, 1H), 7.12-7.31(m, 9H), 8.12 s, br, 1H), 10.10 (s, 1H).

Example 40

2-{2,5-Dioxo-4-[2-(4-phenylacetyl-phenyl)-ethyl]-imidazolidin-1-yl}-N-hydroxy-3-methylbutyramide(40)

The procedure described in method A was followed but using 27m insteadof N-Boc-L-homophenylalanine which gave the title compound (7 mg.)

¹H NMR (300 MHz, CD₃OD): δ 0.91 (d, J=6.6 Hz, 3H), 1.04 (d, J=6.6 Hz,3H), 1.98-2.03 (m, 1H), 2.12-2.16 (m, 1H), 2.78-2.83 (m, 2H), 2.91-2.95(m, 1H), 4.05-4.11 (m, 2H), 4.33 (s, 2H), 7.23-7.38 (m, 7H), 8.01 (d,J=7.8 Hz, 2H).

Example 41N-Hydroxy-2-(4-{2-[4-(1-hydroxyimino-2-phenyl-ethyl)-phenyl]-ethyl}-2,5-dioxoimidazolidin-1-yl)-3-methylbutyramide(41)

To a solution compound 40 (140 mg, 0.32 mmol) in CHCl₃/CH₃OH (10 mL) wasadded HONH₂×HCl (44 mg, 0.64 mmol) and N-methylmorpholine (0.071 mL,0.64 mmol). After stirring for 5 min, one drop of CH₃COOH was added andthe reaction was stirred overnight at room temperature. The solvent wasremoved and the residue was purified by preparative thin layerchromatography to afford the title compound as a white solid (20 mg).

¹H NMR (300 MHz, CD₃OD): δ 0.89 (d, J=6.6 Hz, 3H), 1.03 (d, J=6.6 Hz,3H), 1.89-1.96 (m, 1H), 2.08-2.11 (m, 1H), 2.68-2.73 (m, 2H), 2.91-2.94(m, 1H), 4.04-4.07 (m, 2H), 4.19 (s, 2H), 7.17-7.24 (m, 7H), 7.57 (d,J=7.5 Hz, 2H).

Example 422-(2,5-Dioxo-4-phenethyl-imidazolidin-1-yl)-N-hydroxy-3-methoxybutyramide(42)

The procedure described in method A was followed but using (R)-methyl2-amino-3-methoxybutanoate instead of D-valine methyl esterhydrochloride which gave the title compound (6 mg).

¹H NMR (300 MHz, CDCl₃): δ 1.13 (d, J=6.3 Hz, 3H), 2.01-1.91 (m, 1H),2.19-2.10 (m, 1H), 2.74-2.69 (m, 2H), 3.40 (s, 3H), 4.11-4.04 (m, 1H),4.33-4.26 (m, 1H), 4.51-4.46 (m, 1H), 6.83 (s, 1H), 7.30-7.16 (m, 5H),8.46-8.24 (m, 1H), 9.77 (s, 1H).

Example 43

N-hydroxy-3-methyl-2-hydroxy-(5-oxo-4-phenethyl-2-thioxo-imidazolidin-1-yl)-butyramide

Method H

Step a

Under nitrogen, to a solution of 1b (440 mg, 1.50 mmol) in CH₂Cl₂ (15mL) prepared according to Method A above, was added1,1′-thiocarbonyldiimidazole (1.34 g, 7.52 mmol). The mixture wasstirred at room temperature for 3 h and concentrated under reducedpressure. The residue was diluted with EtOAc and washed with brine. Theputative diastereomers at the valine alpha carbon co-migrate under TLCand were confirmed by NMR below. The organic layer was dried andconcentrated under reduced pressure. The residue was purified by silicagel column chromatography to afford the title compound as a pale yellowoil (200 mg, 40%).

¹H NMR (300 MHz, CDCl₃): δ 0.87, 0.88 (for two epimers, d, J=6.6 Hz,3H), 1.20, 1.21 (for two epimers, d, J=6.6 Hz, 3H), 2.01-2.12 (m, 1H),2.21-2.33 (m, 1H), 2.72-2.85 (m, 3H), 3.71 (s, 3H), 4.08-4.16 (m, 1H),4.92, 4.94 (for two epimers, d, J=9.0 Hz, 1H), 7.19-7.36 (m, 5H).

Step b

To a solution of the above obtained compound (200 mg, 0.6 mmol) indioxane (2.5 mL) was added 10 mL of 6N HCl. The mixture was stirred at90° C. for 2 days. The reaction solvent was removed under reducedpressure. The residue was purified by flash silica gel columnchromatography to afford the title compound as a pale yellow oil (160mg, 83%).

¹H NMR (300 MHz, CDCl₃): δ 0.88 (d, J=6.6 Hz, 3H), 1.21 (d, J=6.6 Hz,3H), 1.94-2.06 (m, 1H), 2.16-2.30 (m, 1H), 2.57-2.88 (m, 3H), 4.04-4.14(m, 1H), 4.99, 5.01 (for two epimers, d, J=9.3 Hz, 1H), 7.16-7.32 (m,5H), 8.57 (d, J=10.8 Hz, 1H), 9.84 (s, br, 1H).

Step c

A solution of the above obtained compound (160 mg, 0.50 mmol) in DMF (5mL) was added N-methylmorpholine (0.23 mL, 2.09 mmol). The mixture wascooled to 0 degrees and BOP (250 mg, 0.57 mmol) added. After stirringfor 30 min at 0 degrees HONH₂×HCl (73 mg, 1.04 mmol) was added. Thereaction was then allowed to warm to room temperature and stirredovernight. The reaction solvent was removed under reduced pressure. Theresidue was diluted with EtOAc, washed with 1N HCl, saturated NaHCO₃ andbrine, dried over anhydrous Na₂SO₄, and concentrated under reducedpressure. The obtained residue was carefully purified by silica gelcolumn chromatography to afford two epimers of the title compound bothas a pale yellow oil (60+60 mg, 72%). Conventional preparative HPLCwould allow purification of the diastereomers.

Less polar epimer: ¹H NMR (300 MHz, CD₃OD): δ 0.88 (d, J=6.6 Hz, 3H),1.07 (d, J=6.6 Hz, 3H), 1.95-2.17 (m, 2H), 2.61-2.76 (m, 2H), 3.06-3.14(m, 1H), 4.16 (t, J=5.1Hz, 1H), 4.79 (d, J=11.1Hz, 1H), 7.15-7.30 (m,5H).

More polar epimer: ¹H NMR (300 MHz, CD₃OD): δ 0.88 (d, J=6.6 Hz, 3H),1.07 (d, J=6.6 Hz, 3H), 1.91-2.18 (m, 2H), 2.65-2.77 (m, 2H), 3.01-3.11(m, 1H), 4.10 (dd, J=5.1Hz, 7.2 Hz, 1H), 4.89 (d, J=11.1Hz, 1H),7.16-7.32 (m, 5H).

Biological Examples

A typical MMP-12 enzyme assay employs recombinant human MMP-12 catalyticdomain expressed and purified as described by Parkar A. A. et al,(2000), Protein Expression and Purification, 20:152. The purified enzymecan be used to monitor inhibitors of activity as follows: MMP-12 (50ng/ml final concentration) is incubated for 60 minutes at roomtemperature with the synthetic substrateMac-Pro-Cha-Gly-Nva-His-Ala-Dpa-NH₂ in assay buffer (0.1 M “Tris-HCl”(trade mark) buffer, pH 7.3 containing 0.1 M NaCl, 20 mM CaCl₂, 0.020 mMZnCl and 0.05% (w/v) “Brij 35” (trade mark) detergent) in the presence(5 concentrations) or absence of inhibitors. Activity is determined bymeasuring the fluorescence at λ_(ex) 320 nm and λ_(em) 405 nm. Percentinhibition is calculated as follows: % Inhibition is equal to the(Fluorescence_(plus inhibitor)−Fluorescence_(background)); divided bythe (Fluorescence_(minus inhibitor)−Fluorescence_(background));

A favoured assay employs full length recombinant human MMP-12, aminoacid residues 1 to 470 (Shapiro et al 1993, J Biol Chem 268:23824-23829)expressed in mouse myeloma cell line NS-40. The purified rhMMP-12typically has the N terminal sequence L₁₇PLNSSTSLE and an SDS-PAGEapparent molecular mass of approx. 56 kDa. Such proteins are availablefrom R&D Systems, USA as a lyophilised 0.2 um filtered solution of 25 mMMES, 0.15M NaCl, 10 mMCaCl₂, 0.15% Brij 35, pH 5.5. Auto-activation ofthe rhMMP-12 can be achieved by dilution to 0.05 mg/ml into TCNB buffer(50 mMTris, 10 mM CaCl₂, 0.15M NaCl, 0.05% Brij 35, pH 7) and incubationat 37 degrees for 30 hours. A preferred buffer for MMP work is 50 mMTris.HCl, pH 7.5, 200 mM Ca acetate.

Suitable FRET substrates include(7-methoxycoumarin-4-yl)acetyl-Pro-Leu-Gly-Leu-(3-(2,4-dinitrophenoyl)-L-2,3-diaminopropionyl)-Ala-Arg-NH₂,commercially available from R&D Systems, USA. Typical specificactivities are >500 picomol/min/ug, with rhMMP-12 measured with 10 uM ofthis substrate, 20 ng activated enzyme in 100 ul TCNB buffer at roomtemperature.

An alternative general MMP substrate is Dnp-PLGLWλ_(D)—R—NH₂.

Counterscreening for MMP selectivity is carried out analogously to theabove using commercially available recombinant enzymes (R& D SystemsUSA) such as MMP-1, 2 & 9 (same substrate as MMP-12) or 3 & 10(substrate: Mca-RPKPVE-Nva-WRK(Dnp)-AR-NH₂).

For example, Table 1 shows the Ki-value expressed in nM for arepresentative selection of compounds according to the invention whentested in an MMP-12 enzyme assay such as those described above. CategoryA indicates ≦50 nM inhibition, category B indicates 51-200 nM inhibitionand category C indicates >200 nM:

Example No. Ki  7 B 10 A 14 A 15 B 25h C 26 A 28 A 29 A 30 A 31 A 33 A34 A 36 A 37 A 38 A 39 A 40 A

Selectivity Profiles

To evaluate the enzymatic inhibition of Tumour Necrosis Factor-αConverting Enzyme (TACE) exhibited by the compounds, an assay wherein aFRET substrate was utilized to generate a spectroscopic response topeptidase cleavage. The activity was measured by a continuous detectionof increased fluorescence intensity during 12 min. The substrateconsisted of a peptide with a fluorescent donor 7-methoxycoumarin (Mca)and a quenching acceptor 2,4-dinitrophenyl group (Dpa), typicallyMca-P-L-A-Q-A-V-Dpa-R-S-S-S-R-NH₂ (R&D Systems, ES003).The cleavage siteby TACE is the peptide bond between Ala and Val. The compounds weretested at a range of concentrations while the enzyme and substrateconcentrations were fixed. A typical TACE assay employs recombinanthuman TACE (supplied by R&D Systems) in an assay buffer (25 mM Tris-HCl,pH=9.0, 2.5 μM ZnCl₂, 0.005% Brij 35). The enzyme concentration (TACE)used was 100 ng/ml, the substrate was prepared at a 100 μM stocksolution in DMSO and a 96-well polypropylene plate was used for thereaction mixtures. To each well of the plate was added assay buffer90,00, enzyme (TACE) 0,09 μl and inhibitor 10. The reactions werestarted by addition of substrate 10 μl/well, giving a substrateconcentration of 10 μM and a total volume of 100 μl/well. The totalconcentration of DMSO was not above 1%. The assay was performed atambient temperature. Product fluorescence (emission filter 320 nM,excitation filter 405 nM) was monitored with a Thermo LabsystemsFluoroskan Ascent plate reader. The Ki was determined by Prism Software.

To evaluate the enzymatic inhibition of Human Matrix Metalloproteinase(MMP-3) exhibited by the compounds, an assay wherein FRET was utilizedto generate a spectroscopic response to peptidase cleavage, was used.The activity was measured by a continuous detection of increasedfluorescence intensity during 12 min. The substrate consisted of apeptide with a fluorescent donor 7-methoxycoumarin (Mca) and a quenchingacceptor 2,4-dinitrophenyl group (Dpa), typicallyMca-Arg-Pro-Lys-Pro-Val-Glu-Nval-Trp-Arg-Lys(Dnp)-NH₂ (R&D Systems,ES002).The cleavage site by MMP-3 is the peptide bond between Glu andNval. The compounds were tested at a range of concentrations, the enzymeconcentration (MMP-3) was fixed at 400 ng/ml and the substrateconcentrations was 10 μM. The MMP-3 assay used employs recombinant humanMMP-3 (supplied by R&D Systems) in an assay buffer of 50 mM Tris-HCl,200 mM calcium acetate at pH=7.5. The MMP-3 enzyme was preactivated bydilution to 0.119 mg/ml into 1 mM APMA (p-aminophenylmercuric acetate)followed by incubation at 37° C. for 24 hours. The substrate wasprepared at a 100 μM stock solution in DMSO and a 96-well polypropyleneplate was used for the reaction mixtures. To each well of the plate wasadded assay buffer 90.00, enzyme (MMP-3) 0.3 μl and inhibitor 1 μl. Thereactions were started by addition of substrate, 10 μl/well, to a totalvolume of 100 μl/well. The total concentration of DMSO was not above 1%.The assay was performed at ambient temperature. Product fluorescence(emission filter 320 nM, excitation filter 405 nM) was monitored with aThermo Labsystems Fluoroskan Ascent plate reader. The Ki was determinedby Prism Software.

The selectivity for MMP-12 over MMP-3 and TACE was evaluated for arepresentative selection of the compounds of the invention by comparingthe Ki figures obtained when tested in the corresponding enzyme assays,such as those described above. The selectivity is presented as the folddifference in Ki for TACE and MMP-3 compared to MMP-12 and is calculatedas the ratio Ki_((TAcE))/Ki_(MMP-12) and Ki_(MMP-3))/Ki_(MMP-12)respectively. The result is summarized in Table 2.

Ki_((TACE))/ Ki_((MMP-3))/ Example Ki_((MMP-12)) Ki_((MMP-12))  1 380140  5 >4500 71  7 >80 53 10 >150 34 12 245 122 13i >190 >19014 >500 >500 15 >700 120 30 2200 75 32 140 >200 36 280 240 38 390 150

1. A compound of the formula I:

wherein; R¹ is C₁-C₆alkyl, C₀-C₃alkandiylcarbocyclyl,C₀-C₃alkandiylheterocyclyl, R² is carbocyclyl or heterocyclyl; R³ is Hor C₁-C₄alkyl; R⁴ is H or C₁-C₄alkyl; each R⁵ and R^(5′) isindependently H, C₁-C₄alkyl or halo; or R⁴ and an adjacent R^(5′)together define a double bond; each R⁶ and R^(6′) is independently H,C₁-C₄alkyl or halo; or R⁵ and an adjacent R⁶ together define a doublebond; or R⁵, R^(5′) and an adjacent R⁶ and R^(6′) together define atriple bond; n is 1-3, m is 0-3; D is absent, or D is an ether,thioether, amine, amide, carbamate, urea or sulphonamide linkage;whereby the group (CR⁵R^(5′))_(n)-D-(CR⁶R^(6′))_(m) has at least 2 chainatoms; X and Y are independently O or S; and wherein each C₁-C₄alkyl isoptionally substituted with 1 to 3 halo or an hydroxyl; each C₁-C₆alkyl,carbocyclyl or heterocyclyl (including those in anyC₀-C₃alkanediylcarbocyclyl or C₀-C₃alkanediylheterocyclyl groups) isindependently optionally substituted with 1 to 3 substituents selectedfrom halo, oxo, cyano, azido, nitro, C₁-C₆alkyl,C₀-C₃Alkdiylcarbocyclyl, C₀-C₃Alkdiylheterocyclyl, Z—NRaRb, Z—O—Rb,Z—S—Rb, Z—C(═NOH)Rb, Z—C(═O)Rb, Z—(C═O)NRaRb, Z—NRaC(═O)Rb,Z—NRaSO_(p)Rb, Z—S(═O)_(p)Rb, Z—S(═O)_(p)NRaRb, Z—C(═O)ORb,Z—OC(═O)RbZ—NRaC(═O)ORb or Z—OC(═O)NRaRb; wherein; each C₀-C₃Alkdiyl isindependently a bond, a C₁-C₃ straight or branched, saturated carbonchain or a C₂-C₃ straight or branched unsaturated carbon chain; thecarbocyclyl or heterocyclyl moiety of any C₀-C₃Alkdiylcarbocyclyl,C₀-C₃Alkdiylheterocyclyl is optionally substituted 1 to 3 times withsubstituents selected from halo, oxo, cyano, azido, nitro, C₁-C₄alkyl,Z—NRaRc, Z—O-Rc, Z—S-Rc, Z—C(═O)Rc, Z—(C═O)NRaRc, Z—NRaC(═O)Rc,Z—NRaSO_(p)Rc, Z—S(═O)_(p)Rc, Z—S(═O)_(p)NRaRc, Z—C(═O)ORc, Z—OC(═O)Rc,Z—NRaC(═O)ORc, or Z—OC(═O)NRaRc; each Z is independently a bond orC₁-C₃alkanediyl; each Ra is independently H or C₁-C₄alkyl; each Rb isindependently H or C₁-C₆alkyl, C₀-C₃Alkdiylcarbocyclyl,C₀-C₃Alkdiylheterocyclyl; or Ra and Rb together with an adjacent N atomdefine pyrrolidine, piperidine, morpholine, piperazine or N-methylpiperazine; Rc is H or C₁-C₄alkyl; or Rc and Ra together with anadjacent N atom define pyrrolidine, piperidine, morpholine, piperazineor N-methyl piperazine each p is independently 1 or 2; andpharmaceutically acceptable salts and solvates thereof.
 2. A compoundaccording to claim 1, wherein R¹ is optionally substituted, branchedC₂-C₆alkyl.
 3. A compound according to claim 2, wherein the alkylbranches at position 1, especially wherein R¹ is —CH(CH₃)₂, —C(CH₃)₃ or—CH(CH₃)(CH₂CH₃).
 4. A compound according to claim 1, wherein theC₀-C₃alkandiylcarbocyclyl as R¹ is carbocyclylmethyl- or preferablycarbocyclyl; or the C₀-C₃alkandiyleterocyclyl as R¹ isheterocyclylmethyl- or preferably heterocyclyl.
 5. A compound accordingto claim 4, wherein each carbocyclyl is (optionally substituted);phenyl, cyclopentyl or cyclohexyl; or each heterocyclyl is (optionallysubstituted); pyrrolyl, pyrrolinyl, pyrrolidinyl, pyridyl, pyrimidinyl,piperidyl piperazinyl, thiazolyl or morpholinyl.
 6. A compound accordingto claim 5, wherein R¹ is cyclohexyl or cyclopentyl.
 7. A compoundaccording to claim 1, wherein the steric center whereto R¹ is attachedhas the R stereochemistry.
 8. A compound according to claim 1, wherein Xand/or Y are O, preferably wherein both X and Y are O.
 9. A compoundaccording to claim 1, wherein the steric center of the imidazoline ringto which the —(CR⁵R^(5′))_(n)-D-(CCR⁶R^(6′))_(m)—R² group is attached,has the S stereochemistry.
 10. A compound according to claim 1, whereinD is an ether linkage or D is absent.
 11. A compound according to claim1, wherein the —(CR⁵R^(5′))_(n)-D-(CR⁶R^(6′))_(m)— group has in total 2or 3 chain atoms.
 12. A compound according to claim 11, wherein n and mare 1 and D is absent.
 13. A compound according to claim 12, wherein R⁵,R^(5′), R⁶ and R^(6′) are H
 14. A compound according to claim 1, whereinR² is an optionally substituted, aromatic monocyclic ring, especiallyphenyl, pyrrolyl, thiazolyl, pyridyl or pyrimidinyl.
 15. A compoundaccording to claim 14, wherein an optional substituent to R² is (orthoor meta); C₁-C₄alkyl, haloC₁-C₂alkyl, —C(═O)C₁-C₃alkyl, C₁-C₃alkoxy orhalo.
 16. A compound according to claim 14, wherein R² is optionallysubstituted phenyl.
 17. A compound according to claim 16, wherein anoptional substituent to R² is fluoro in the ortho position.
 18. Acompound according to claim 14, wherein an optional substituent to R² isan aromatic monocyclic ring, which ring is in the para position and isoptionally substituted with C₁-C₄alkyl, haloC₁-C₂alkyl, C(═O)C₁-C₃alkyl,C₁-C₃alkoxy or halo.
 19. A compound according to claim 18, wherein thearomatic monocyclic ring is bonded to R² via a methylene, ethylene or—O— linkage.
 20. A compound according to claim 18, wherein the aromaticmonocyclic ring is bonded to R² via a —C(═O)CH₂— or CH₂C(═O)— linkage.20a. A compound according to 18, wherein the compound further comprisesa fluoro substituent in the ortho position.
 21. A compound according toclaim 1, wherein R³ and/or R⁴ is H.
 22. A compound according to claim 3,wherein the compound is:2-(2,5-Dioxo-4-phenethylimidazolidin-1-yl)-N-hydroxy-3-methyl-butyramide;2-{4-[2-(2-Fluorophenyl)-ethyl]-2,5-dioxoimidazolidin-1-yl}-N-hydroxy-3-methyl-butyramide;2-[2,5-Dioxo-4-(2-p-tolylethyl)-imidazolidin-1-yl]-N-hydroxy-3-methylbutyramide2-{4-[2-(2-Fluoro-4-methylphenyl)-ethyl]-2,5-dioxoimidazolidin-1-yl}-N-hydroxy-3-methylbutyramide2-{4-[2-(4-Benzylphenyl)-ethyl]-2,5-dioxoimidazolidin-1-yl}-N-hydroxy-3-methyl-butyramide2-{4-[2-(4-Benzyl-2-fluorophenyl)-ethyl]-2,5-dioxoimidazolidin-1-yl}-N-hydroxy-3-methylbutyramide2-{2,5-Dioxo-4-[2-(4-phenoxyphenyl)-ethyl]-imidazolidin-1-yl}-N-hydroxy-3-methylbutyramide2-{4-[2-(2-Fluoro-4-phenoxyphenyl)-ethyl]-2,5-dioxoimidazolidin-1-yl}-N-hydroxy-3-methylbutyramide2-{2,5-Dioxo-4-[2-(4-phenylacetylphenyl)-ethyl]-imidazolidin-1-yl}-N-hydroxy-3-methylbutyramide2-{4-[2-(2-Fluoro-4-phenylacetyl-phenyl)-ethyl]-2,5-dioxoimidazolidin-1-yl}-N-hydroxy-3-methylbutyramide2-(2,5-Dioxo-4-phenethylimidazolidin-1-yl)-3-methylpentanoic acidhydroxyamide2-{4-[2-(2-Fluorophenyl)-ethyl]-2,5-dioxoimidazolidin-1-yl}-3-methylpentanoicacid hydroxyamide2-[2,5-Dioxo-4-(2-p-tolylethyl)-imidazolidin-1-yl]-3-methyl-pentanoicacid hydroxyamide2-{4-[2-(2-Fluoro-4-methylphenyl)-ethyl]-2,5-dioxoimidazolidin-1-yl}-3-methyl-pentanoicacid hydroxyamide2-{4-[2-(4-Benzylphenyl)-ethyl]-2,5-dioxoimidazolidin-1-yl}-3-methyl-pentanoicacid hydroxyamide2-{4-[2-(4-Benzyl-2-fluorophenyl)-ethyl]-2,5-dioxoimidazolidin-1-yl}-3-methyl-pentanoicacid hydroxyamide2-{2,5-Dioxo-4-[2-(4-phenoxyphenyl)-ethyl]-imidazolidin-1-yl}-3-methyl-pentanoicacid hydroxyamide2-{4-[2-(2-Fluoro-4-phenoxyphenyl)-ethyl]-2,5-dioxoimidazolidin-1-yl}-3-methyl-pentanoicacid hydroxyamide2-{2,5-Dioxo-4-[2-(4-phenylacetyl-phenyl)-ethyl]-imidazolidin-1-yl}-3-methyl-pentanoicacid hydroxyamide2-{4-[2-(2-Fluoro-4-phenylacetyl-phenyl)-ethyl]-2,5-dioxoimidazolidin-1-yl}-3-methyl-pentanoicacid hydroxyamide2-(2,5-Dioxo-4-phenethyl-imidazolidin-1-yl)-N-hydroxy-3,3-dimethylbutyramide2-(2,5-Dioxo-4-phenethyl-imidazolidin-1-yl)-N-hydroxy-3,3-dimethylbutyramide2-[2,5-Dioxo-4-(2-p-tolylethyl)-imidazolidin-1-A-N-hydroxy-3,3-dimethylbutyramide2-{4-[2-(2-Fluoro-4-methylphenyl)-ethyl]-2,5-dioxoimidazolidin-1-yl}-N-hydroxy-3,3-dimethylbutyramide2-{4-[2-(4-Benzylphenyl)-ethyl]-2,5-dioxoimidazolidin-1-yl}-N-hydroxy-3,3-dimethyl-butyramide2-{4-[2-(4-Benzyl-2-fluorophenyl)-ethyl]-2,5-dioxoimidazolidin-1-yl}-N-hydroxy-3,3-dimethylbutyramide2-{2,5-Dioxo-4-[2-(4-phenoxyphenyl)-ethyl]-imidazolidin-1-yl}-N-hydroxy-3,3-dimethyl-butyramide2-{4-[2-(2-Fluoro-4-phenoxyphenyl)-ethyl]-2,5-dioxoimidazolidin-1-yl}-N-hydroxy-3,3-dimethylbutyramide2-{2,5-Dioxo-4-[2-(4-phenylacetylphenyl)-ethyl]-imidazolidin-1-yl}-N-hydroxy-3,3-dimethylbutyramide2-{4-[2-(2-Fluoro-4-phenylacetylphenyl)-ethyl]-2,5-dioxoimidazolidin-1-yl}-N-hydroxy-3,3-dimethylbutyramide23. A compound according to claim 5a, wherein the compound is:2-Cyclohexyl-2-(2,5-dioxo-4-phenethyl-imidazolidin-1-yl)-N-hydroxy-acetamide2-Cyclohexyl-2-{4-[2-(2-fluorophenyl)-ethyl]-2,5-dioxoimidazolidin-1-yl}-N-hydroxy-acetamide2-Cyclohexyl-2-[2,5-dioxo-4-(2-p-tolylethyl)-imidazolidin-1-yl]-N-hydroxy-acetamide2-Cyclohexyl-2-{4-[2-(2-fluoro-4-methylphenyl)-ethyl]-2,5-dioxoimidazolidin-1-yl}-N-hydroxy-acetamide2-{4-[2-(4-Benzylphenyl)-ethyl]-2,5-dioxoimidazolidin-1-yl}-2-cyclohexyl-N-hydroxy-acetamide2-{4-[2-(4-Benzyl-2-fluorophenyl)-ethyl]-2,5-dioxoimidazolidin-1-yl}-2-cyclohexyl-N-hydroxy-acetamide2-Cyclohexyl-2-{2,5-dioxo-4-[2-(4-phenoxyphenyl)-ethy]-imidazolidin-1-yl}-N-hydroxy-acetamide2-Cyclohexyl-2-{4-[2-(2-fluoro-4-phenoxyphenyl)-ethyl]-2,5-dioxoimidazolidin-1-yl}-N-hydroxy-acetamide2-Cyclohexyl-2-{2,5-dioxo-4-[2-(4-phenylacetylphenyl)-ethyl]-imidazolidin-1-yl}-N-hydroxy-acetamide2-Cyclohexyl-2-{4-[2-(2-fluoro-4-phenylacetylphenyl)-ethyl]-2,5-dioxoimidazolidin-1-yl}-N-hydroxy-acetamide24. A pharmaceutical composition comprising a compound of formula (I) ora pharmaceutically acceptable salt or solvate thereof, as claimed in anyone of claim 1 to 23 in association with a pharmaceutically acceptableadjuvant, diluent or carrier.
 25. A process for the preparation of apharmaceutical composition as claimed in claim 24, which comprisesmixing a compound of formula (I) or a pharmaceutically acceptable saltor solvate thereof as defined in any one of claim 1 to 23 with apharmaceutically acceptable adjuvant, diluent or carrier.
 26. A compoundof formula (I) or a pharmaceutically acceptable salt or solvate thereof,as claimed in any one of claim 1 to 23, for use in therapy.
 27. Use of acompound of formula (I) or a pharmaceutically acceptable salt or solvatethereof as claimed in any one of claim 1 to 23, in the manufacture of amedicament for use in the treatment of an obstructive airways disease.28. Use according to claim 27, wherein the obstructive airways diseaseis asthma or chronic obstructive pulmonary disease.
 29. A method oftreating a disease or condition mediated by MMP-12 which comprisesadministering to a patient a therapeutically effective amount of acompound of formula (I) or a pharmaceutically acceptable salt or solvatethereof, as claimed in any one of claim 1 to
 23. 30. A method oftreating an obstructive airways disease which comprises administering toa patient a therapeutically effective amount of a compound of formula(I) or a pharmaceutically acceptable salt or solvate thereof, as claimedin any one of claim 1 to
 23. 31. A method according to claim 30, whereinthe obstructive airways disease is asthma or chronic obstructivepulmonary disease.